To some of us, plunking down a few hundred dollars every three or four years to upgrade our systems comes as naturally as filling our gas tanks, buying two dollar menu cheeseburgers instead of a $3 double cheeseburger because it saves money, and shielding our eyes when we go out in the sunlight. Then again, if you don’t have the money to upgrade, or you don’t have the means to upgrade, nothing is more painful than your favorite MMO announcing that you are being left behind due to the natural progression of updates. Your Pentium 3 processor may still play Half Life 2 just fine, but if your favorite MMO wants to continue progression, the lower tiers are going to be left behind.
For Eve Online, this equates to a little over 1,000 customers. Due to Eve Online’s upgrade to the SSE2 instruction set, incompatible processors are no longer being supported. This list includes Pentium 3 and older, and AMD Athlon XP and older. Athlon 64 CPUs are reportedly not affected. It is worth noting that these CPUs are from 2003 and beyond, making them older than Eve Online itself.
You can read more about it in the short dev blog here. More on Eve Online as it appears.
MMO Fallout 
Honestly, this is kind of a non-story. EvE has been mostly unplayable on old hardware since the last graphical update anyway.