The difficulty will not increase for the next step (tomorrow morning or at noon the next difficulty step will begin). At most, you'll see a 1-2% change which can go either way - right now it's estimated it will go down 1%, but that can change. Difficulty for the next step will be pretty much the same as it is now.

ASIC's are far too big of an investment for many people to make, at least at this time, when FPGA mining is just starting to take off. Make no mistake, ASIC's are THE end-game for Bitcoin mining. Eventually, a few miners that manage to invest enough money in ASIC's will grab most of the hashing power of the network, but right now we need to pass through the FPGA adoption era.

GPU's WILL become obsolete, but I don't think it will be in the next couple of months. It will take a little bit longer, but by the end of 2012, especially with the reward halving, I estimate that very few people will find that mining with GPU's is profitable.

[edit] BFL is most definitely not causing any difficulty disruptions. They shipped far too few units so far to make even a dent in the hashing power.