I've always been one to live now and worry later in this regard. Canon makes some very fine EF-S mount lens as well as some of the third party ones too. I don't really see Canon abandoning the APS-C sensor anytime in the near future as a lot of Wildlife Photographers prefer the crop sensor vs the FF.
Might be a while before theres a FF sensor in the $1000 range to as its quite expensive to manufacture over the smaller one.
Fully agreed. Even though I am a full frame user I still keep some EF-S gear around and if I could afford it, I'd probably add a little bit more EF-S stuff! 30D.. *scratch head*
After Canon took all the pains to develop and launch the 17-55 f/2.8 IS, it would not make sense to dump the EF-S line. The lens is targeted at professional users (according to them) and comes with a professional price tag (whether or not it is worth it is a subjective value judgement). Based on the construction of the lens and the amount of exotic glass involved, I would hazard a guess that it is not exactly cheap to design and build.. Canon wouldn't throw away the R&D investment like that. It makes no sense from a business perspective. As some have pointed out, they are in the game to make money so there are sound financial reasons.
If you DO go full frame, you will be able to let go of your EF-S gear without too much of a financial penalty. In the meantime you'll be able to get great photos. I'm speaking as someone who went this route. A totally unexpected opportunity gave me a shot at full frame. No I did not suffer too much when letting go of my 10-22. Well, financially that is. Emotionally.. is a different thing
FF is not a replacement for APS-C but rather a complement. So there will continue to be an EF-S market.
The kit lens is cheap in construction and price, but represents surprisingly good value namely because the price is so low. Stop it down to f/8 and it can produce some pretty amazing results - others have taken photos with it that I simply cannot believe came out of a $80 piece of glass. As for build quality..... so many love the 50 f/1.8 which is every bit as cheap feeling, but it has superb glass.