Technically (and therefore financially?) it might make more sense, from a computing point of view. I don't know what the technology is now, but we used to take activity of a file into consideration. Like that's why google gets back to you faster now, cuz it doesnt look at the whole world, it first looks at your usual stuff. So I see this as a paradigm shift for pc - reacting to how we are actually using the site and changing in accordance. Not that reacting is a paradigm shift - that IS part of the fabric of pc! But pc is moving. Cool! Change, people! Change or die! Maybe evilution didn't happen x years ago, but it's happening now!