It's about time to get a new one. Older gpus don't sli as efficiently as the current gen and a mid range card from both nvidia and ati will show you a HUGE improvement.
CrossfireX is a ATI technology for ATI cards... And the compatibility is not even that big. You still need to use cards from the same series with similar specs.
"There is enough on earth for everybody's need, but not for everyone's greed." - Mohandas Gandhi
The Fermi Geforce 460 GTX is a good choice, don't put it in to SLI or phsyx with the 9500, it'll just result in motherboard and driver issues with 9/10 games.