Originally Posted by
Moinaldo
You could get a GTX660 or HD7870 but they are a little more expensive than what you say you want to spend, around $230... if you like to OC your card you should get the 7870, if you will just leave it as it is out of the box, I'd suggest getting the 660... but let me tell you that you won't be getting 100fps in a very high populated orgrimmar, more likely to get around 70-80.
You can always sell the card you have right now and maybe get a gtx670/hd7950, or you can wait until the next gen arrives just like shroudster posted, however rumors say next generation wont have any big performance improvements over the 6xx/7xxx series, because they will continue to be 28nm tech.