Building a new pc in time for Christmas and I have everything apart from the graphics.. I was thinking of getting a
MSI GTX 560Ti Twin Frozr 1GB and SLi in the near future

Will be used for gaming at a resolution of either 720p or 1080p.. Since my TV doesn't support anything higher.. at least I think lol but then this old Radeon x1100 is useless... I won't be using any mega high resolutions so 560Ti should be good enough to max out most games at those resolutions..

Any recommendations for an equally priced card and with SLi/Crossfire for the future?

Specs of the new system..
Motherboard: Asus M5A97 PRO with Corsair HX 750W PSU
CPU: AMD Phenom II x6 1090T BE @ 3.2GHz
RAM: 8GB (2x4GB) Corsair Vengence 1600MHz
HDD: Hitachi Deskstar 500GB + Crucial C300 64GB SSD
(Not the best hard drive but I already had it and it performed fine enough in my old system so it will do lol, SSD will speed somethings up though.)

I believe Asus HD 6950 DirectCU II 1GB is better option and cheaper (here in Greece)
Also your motherboard doesnt support SLI, only CrossfireX and isnt a good option either because the second PCIe works at 4x when you put two graphic cards.
http://www.asus.com/Motherboar ... M5A97_PRO/#specifications