I currently have a T2i but would like something more 'Professional'. Of course I dream of a 5D ii but I am worried I will not be able to use the lenses I just bought. Am I correct in that as long as they are EF and NOT EF-S they will work on both cameras?? I am researching the differences between the 7D and 5D ii, (if anyone has an input, that'd be great)! Thanks!
You are correct in the fact you'll need EF lenses for full frame. As for the 7D vs 5D2 what is your intended use & is high ISO important etc? They are both very good but in different ways especially if trying to shoot sports or wildlife from a distance.