PhysX - Is a PhysX card necessary?

It seems like there aren't too many current titles supporting PhysX technology. On the Geforce.com site they mention all these different arrangements with different development houses (ie EA), though I'm still not seeing too many titles released using this technology.

Does anyone know of any upcoming significant releases that will be PhysX capable (Battlefield 3?)?
 
It all depends on what games that you are playing and your system specs. In such games physx can really have a large overhead especially in the newest titles while the original titles have every low overhead. In Mafia 2 you might want a dedicated card to free up the main card for rendering only ect aka more fps. Batman and metro is the same way. Typically any thing above a 8800/9800gt is a waste but a gts250/450 is as far as people should go. It does make a difference but in 95% of the over all titles available on the market for the past decade it won't make a difference.