It’s my believe that the economic downturn will be much worse than it is today, and that 50-80% of the venture-backed startups currently
operating will shut down or go on life-support (i.e. 3-4 folks working
on them) within the next 18 months.

Make a list of every Web 2.0 startup to raise an A or B round and
cross 80% of them off the list, because they will not make it to their
next round of funding or profitability.