After holding out for a long time, Twitter, Facebook and MySpace are now falling in (like dominoes) to provide feeds to search engines for real time search. Makes sense, the search engines had to get just one of these to get the others to fall in line. The public bloggers (and in this case micro-bloggers) do suffer from varying bouts of narcissm or maybe are lonely or just too desperate to be heard (read 'read') and therfore the advantage to a social network to being visible in real time. Having a rival micro blog network available while you are left behind is a (doubly) huge disadvantage.
Of course, this is one more battle field for Bing and Google. My fear is that both will end up overpaying for this ability to search but can't do without it either.