Jeff’s views on what will happen with the current Web 2.0 start-ups is interesting:

A small number of companies will be acquired early before they reach scale or revenues (as opposed to the current fantasy that GEMAYANI will acquire them by the dozen). Another small number will reach profitability and will have their options open, and the majority will either hit the wall or operate small enough that their founders will be able to keep them running alongside their regular day job.

I personally think that there will be a power law kind of situation. Where the A list gets bought up, the B list manage quite fine on their own thank you very much and the C list keep running as a side job.