IMHO, it really just depends on if you are planning to print your photos any larger than about 6×4.
I am using a 2MP camera at the moment, but because I never print my photos and only view them on monitors it is more than enough resolution for me. I am upgrading soon, but only to a 3MP camera becuase I am more interested in features than resolution.
As for your comment on prices dropping, I'm afraid this will always happen in the electronics world, you just have to accept it. In time (maybe 12-18 months) 4-5MP cameras will drop to the current prices of 2-3MP ones.