I disagree with the main premise: That as long as you provide the "90% functionality" (i.e mail,chat e.t.c), no casual user will miss the last 10%. Sure, most of the time this will work fine, but occasionally people want more. Maybe upload a video to youtube, or chat on that new up-and-coming social networking site? "The user" is not quite so simpleminded as some here seem to think. More importantly, since the web market can change so fast any static set of features could get sidelined by a new application/web page et al, and it's very hard to predict in advance what the user will want. Therefore, one makes devices that can do everything. This is not an anachronism, it's the only logical solution to a market that changes too fast to lock people in to a very small subset of a computer.