had read this awhile ago. i would personally go for the 295, since it would allow for another 295 in sli in the future.
Gtx 295 Vs Gtx 280 Sli ! ! ! - Overclock.net - Overclocking.net
Good Point even if it would get lower scores than two 280GTX in SLI, then i could add a second 295 in the future, if and when games become more GPU taxing. Which i have read a lot of articles and information that states that games are going to be more GPU intensive in the near future in order to take more load off the CPU.
(Thank you to Muffin Man, and Slaymate for your research)