Click here to see the new: Top 10 free MMORPG to play in 2012

Old top 10:

1 - Runes of Magic

With an extensive range of features Runes of Magic is redefining the standard for free-to-play titles. Runes of Magic conveys an absorbing story through more than 1,600 quests in an exciting and dangerous fantasy world. Runes of Magic is a fantasy MMORPG (Massively Multiplayer Online Role-Playing Game) without monthly costs and free to download. Dive into Taborea, a magical world full of wonders and ancient mysteries.
Play Now: Runes of Magic

2 - The Lord of the Rings Online

The Lord of the Rings Online is now officially free to play. Join with millions of other adventurers as they explore the most complete and authentic recreation of Middle-earth ever created and participate in LOTRO’s award-winning story up to level 50 for free. This major update will also extend the game’s epic story and expand the world of Middle-earth with the new region of Enedwaith while continuing to deliver state-of-the-art graphics and gameplay, as well as a rich set of features that until now could only be found in premium subscription-based online games.
Play Now: The Lord of the Rings Online

3 - Dungeons and Dragons: Online Eberron Unlimited

Dungeons & Dragons Online: Eberron Unlimited introduces a new Free To Play option to the game! Players can download DDO for free and enjoy many free adventures. DDO Unlimited puts players into the heat of battle with full, real-time control over their character’s movement and special attacks.
Play Now: Dungeons & Dragons Online

4 - Vindictus

Vindictus is the first free to play physics-based action multiplayer online action role-playing game developed by devCat studios. Vindictus uses a modified Source Engine to enable interaction with the environment like shattering objects, binding enemies with chains, hurling debris, and piercing defenses with spears. In the game, players will be able to engage in high-speed combat hack and slash style, and experience the stunning visuals.
Play Now: Vindictus

5 - Allods Online

Allods Online features two warring factions, six races, 28 classes, ship vs ship Astral space battles, mini-games-based crafting systems, PvP, PvE, guilds, 6v6 Goblinoball and many other elements. Players who reach level 35 will be able to start building their own massive Astral spaceship. They can then explore the deep and dynamic Astral environment in search of treasure, adventure and new territory, or engage in massive Astral battles featuring dozens of ships, each controlled by a crew of players. With a deep storyline covering thousands of years of in-game history, and over 1,500 quests at release, Allods Online has all the depth to compete with the best subscription MMORPGs on the markets, without any subscription, ever!
Play Now: Allods Online

6 - Perfect World
Perfect World - MMORPGPerfect World International has more than 50 million players worldwide and is one of the most successful 3D MMORPGs. In Perfect World, players can immerse themselves in a huge online world that must be explored to be believed. Deeply rooted in Chinese mythology, the game features unparalleled character customization, extensive costume selection, custom flying mounts, dynamic skill progression, and high-level replay value in the form of territory wars.
Play Now: Perfect World

7 - Dragon Nest

Dragon Nest is a an action MMORPG published by Nexon where great visuals go hand in hand with charming anime characters and real time combat. There’s a lot to be amazed at in this MMORPG and any self-respected fan should try.
Play Now: Dragon Nest

8 - Mabinogi
Mabinogi - MMORPGMabinogi is a 3D cartoony MMORPG with a unique skill system. The game has an innovative aging system where Characters age 1 game year every week in real life. "Mabinogi", offers true-to-life experiences through smooth, animation-like screens and unique characters that sing, make clothes, cook, chop trees, fish, build houses and fight curses that have long plagued Erinn, "Mabinogi’s" fantasy world. To be precise, Erinn is located in northern Europe and based on elements of ancient Celtic myths. NPCs in the "Mabinogi" world remember the players. They act according to how friendly they are with players, who can build relationships with them in various ways.
Play Now: Mabinogi

9 - Dragon Saga
Dragonica - MMORPGDragon Saga is the free arcade-style 3D side-scrolling MMORPG. Developed by Korean developers Barunson Interactive. It features original keyboard-controlled gameplay, combo-based action that rewards skilful players, a vibrant 3D universe and plenty of tongue-in-cheek humour along the way. Dragonica has universal appeal, and is a game for all ages.
Play Now: Dragon Saga

10 - Ragnarok Online
Ragnarok OnlineRagnarok Online allows you to create a virtual character, customize it, and partake in epic adventures across exotic lands. Hang out with your friends or make new ones with an ever-expanding universe, in-game events, and a growing community of users, there are always places to see, things to do, and people to meet in the world of Ragnarok! The game is pay to play, but there are official "Free To Play" servers where players can play Ragnarok Online free of charge (Valkyrie Server Client).
Play Now: Ragnarok Online

Honored Mentions To:

Runescape - MMORPGRuneScape holds the Guinness World Record as the largest free-to-play MMORPG in the world and currently has over 5 million active players, including over 1 million paying subscribers.

Anarchy Online
Anarchy Online - MMORPGAnarchy Online was the first of the major western MMO’s to go for a free-to-play business model in 2004, and through the years Funcom has introduced numerous progressive models.
Anarchy Online have to date entertained more than 1.3 million gamers, and continues to attract new players in the hundreds of thousands. As Anarchy Online goes into its seventh year of operation Funcom also looks ahead, and a great new graphics engine will be launched later this year.

MapleStory - MMORPGLaunched on May 11, 2005, MapleStory became a legend in online games. Players have flocked to MapleStory with over 92 million worldwide users and over six million users in North America. Players have turned MapleStory into an online video mainstay through blogs, community fan sites and fan videos. Over 200,000 videos are available by searching MapleStory at YouTube.

Update: Top 10 free MMORPG to play in 2011

Free MMO Games