The fourteenth installment (not counting spin-offs) of the Final Fantasy series. The second one to be online. Initially received terrible reviews. It has since begun to turn itself around and is becoming more similar to Final Fantasy XI. The game will be F2P until it is up to par with all other MMO's and then will also be released on the PS3.
The class system is even more flexible than it was in XI. One can now change jobs on the fly without returning to their mog houses. Additionally, crafting skills now have their own classes and the crafting system has gotten more complex, requiring one to pay attention to what they are doing while crafting an item instead of just clicking okay once the ingredients are set.
Final Fantasy XIV originally took a lot of heat but it has since come a long way and it will probably become one of the next big MMORPGs. Give it a try while its free!