They are who believes that the free to play model is the future...
This list features some of today’s best pay-to-play MMORPG, games that could be even more successful in case they were free-to-play. Don’t forget to check the free alternatives we recommend for each one. We hope you enjoy it.

World of Warcraft, often referred to as WoW, is a massively multiplayer online role-playing game (MMORPG) by Blizzard Entertainment. World of Warcraft takes place within the Warcraft world of Azeroth, four years after the events at the conclusion of Blizzard's previous Warcraft release, Warcraft III: The Frozen Throne.
With more than 11.5 million monthly subscribers,World of Warcraft is currently the world's largest MMORPG in those terms,and holds the Guinness World Record for the most popular MMORPG.
Free Trial: 10 days free
Official Site: http://www.worldofwarcraft.com (US) http://www.wow-europe.com/en/index.xml (Europe)

Eve Online (officially capitalized EVE Online) is a video game by CCP Games. It is player-driven persistent-world massively multiplayer online game set in a science fiction space setting. Players pilot customizable ships through a universe comprising over eight thousand star systems.Most star systems are connected to one or more other star systems by means of jump gates.
Players of Eve Online are able to participate in any number of in-game professions and activities, including mining, manufacturing, trade, exploration and combat (both player versus environment and player versus player). The range of activities available to the player is facilitated by a character advancement system based upon training skills in real time, even while not logged in to the game.
Free trial: 14 days free
Official Site: http://www.eveonline.com/

The Lord of the Rings Online (commonly abbreviated to LOTRO, LotRO) is a massively multiplayer online role-playing game (MMORPG) set in a fantasy universe based upon J. R. R. Tolkien's Middle-earth writings. It takes place during the time period of The Lord of the Rings.
The Lord of the Rings Online was developed by Turbine and is subscription-based.
Free Trial: Play free for 10 days
Official Site: http://www.lotro.com/ (US) http://www.lotro-europe.com/ (Europe)

Final Fantasy XI also known as Final Fantasy XI Online, is a massively multiplayer online role-playing game (MMORPG) developed and published by Square (later Square Enix) as part of the Final Fantasy series.
The story is set in the fantasy world of Vana'diel, where tasks can be performed to improve a character's powers or to complete quests. Players are able to customize a character that they will guide through the story. There are also thousands of quests that allow players to gain various rewards, as well as a growing number of player versus player competitions.
Free Trial: ?
Official Site: http://www.playonline.com/ff11eu/index.shtml (Europe) http://www.playonline.com/ff11us/index.shtml (American)

Warhammer Online: Age of Reckoning (officially abbreviated as WAR[3]) is a massively multiplayer online role-playing game based on Games Workshop's Warhammer Fantasy setting. It was developed by Mythic Entertainment and simultaneously released in North and South Americas, Europe, Asia, Australia and New Zealand on September 18, 2008.[1] The game revolves around the continual worldwide conflict that the Warhammer Fantasy setting is known for, and the game is geared toward ongoing, constant war laced with dark humor.
Free Trial: 10 days free
Official Site: http://www.warhammeronline.com/ or http://www.war-europe.com/ (Europe)

City of Heroes/City of Villains is a massively multiplayer online role-playing game based on the superhero comic book genre, developed by Cryptic Studios and published by NCsoft. On October 31, 2005 the game's first sequel, City of Villains, was launched, allowing players to play as supervillains.
In the game, players create superhero player characters that can team up with others to complete missions and fight villains belonging to various gangs and organizations in Paragon City and its surrounding areas.
Free Trial: 14 days free
Official Site: http://www.cityofheroes.com/ (American) or http://eu.cityofheroes.com/en/ (Europe)

Age of Conan: Hyborian Adventures is a fantasy-themed massively multiplayer online role-playing game (MMORPG) developed by the Norwegian computer video game developer company Funcom for PCs.
Hyborian Adventures is the first installment in the planned Age of Conan series. Age of Conan itself takes place within the continent of the Hyborian kingdoms, a year after the events depicted in Robert E. Howard's Conan novel, The Hour of the Dragon. Hyborian Adventures' release celebrated the 76th anniversary of the Conan franchise.
Free trial: ?
Official site: http://www.ageofconan.com/

EverQuest II (EQ2), based upon the popular EverQuest, is a fantasy massively multiplayer online role-playing game (MMORPG) developed by Sony Online Entertainment (SOE) and shipped on 8 November 2004. It features graphics and gameplay vastly updated from its predecessor as well as NPCs that speak.
Free Trial: 14 days free
Official Site: http://everquest2.station.sony.com/

Lineage II is a fantasy massive multiplayer online role-playing game (MMORPG) for the PC, and a prequel set 150 years before Lineage. It has become very popular since its October 1, 2003 launch in South Korea, reporting 610,918 unique users during the month of March 2007.
Free trial: ?
Official Site: http://www.lineage2.com (US) http://www.discoverlineage2.com/en/ (Europe)

The Matrix Online (also known as MxO) is a massively multiplayer online game developed by Monolith Productions. It is an official continuation of the The Matrix storyline. The player assume the role of a redpill, a human who was formerly trapped inside the Matrix.
Free Trial: ?
Official Site: http://thematrixonline.station.sony.com/

Ultima Online (UO) is a graphical massively multiplayer online role-playing game (MMORPG), released on September 25, 1997, by Origin Systems. It was instrumental to the development of the genre, and is still running today. The game is played online, in a fantasy setting similar to that of the other Ultima games that preceded it.
Free Trial: ?
Official Site: http://www.uo.com/

Dragon Ball Online (officially abbreviated as DBO) is a massively multiplayer online role-playing game being developed simultaneously in Japan and South Korea by NTL, set in the Dragon Ball universe, first introduced by the Dragon Ball Japanese manga in 1984. Dragon Ball Online takes place on Earth, 216 years after the events at the conclusion of the Dragon Ball manga series.
Series creator Akira Toriyama has a great deal of creative control over the project, both contributing to and supervising the story and art design, including character and location arrangements. It has been stated that Toriyama has been working on character designs for this project for the last five years.
Free Trial: ?
Official Site: http://www.ntl-kk.com