The types of software you should make in 2010/2011
meta.maxkle.in
meta.maxkle.in
This smacks of market timing, which does not work for stocks and does not work here. Not all failures are possible to explain in terms of technology maturity or penetration (e.g. the author's example of YouTube-like sites), nor can you say with certainty a Facebook-clone will fail (there have been many posts and discussions on HN lately precisely on how to succeed at that.)
Instead, I believe the message should be similar to what PG espouses: solve a problem. If the people who have this problem also have money, invite them to pay you for it.
edit: grammar.