I think most users who were going to buy a blu-ray player within the next few years have already bought a PS3 for that purpose. Most consumers aren't early adopters and won't buy something unless there is a real reason to.
All the new releases still come out on DVD, rentals are mainly DVD and to those who aren't technically inclined, they don't really care about the format as long as it plays movies.
Sony isn't going to overtake Microsoft until they not only have better games, but they also have something that shows gamers that don't follow tech that it's better than their PS2. Right now, there aren't many games that really improve mechanics vastly on the PS3 vs the previous generation. Games like Gears of War on the 360 were not only a graphical improvement, they were a mechanics shift. Until the PS3 has titles that differentiate itself from the same old stale games, you might as well stick with your PS2.
I don't think the PS3 will ever overtake the 360. People think it will because Sony has done well in the past. I think the PS3 will sell the least of the big 3.