According to VentureWire,

A plague of layoffs touching all industries - specifically the finance and technology sectors - has opened the flood gates for entrepreneurs looking to strike out on their own at a time when jobs are scarce. Some cases are desperation, while others are an opportunity for talented executives to take the start-up plunge they always dreamed of.

Only time will tell, if there is really a large wave of new start-up activity. My entirely subjective sense is that it may never be a good time to do a start-up, but some times are worse than others. If you can bootstrap or if you have access to angel (or here is an unlikely thought) VC money, now may be a good time to start on the theory that you wont need market traction for a year or more and you can catch the next wave. If you don’t have a brilliant business plan and you expect to get professional investment, it will be very hard to find. My sense is that investors are not feeling a lot of pressure to invest right away. They are actually looking at fewer opportunities (even though there may be more out there) and they are looking longer and harder at them.