I agree some of the anticipated features are unproven as of yet, but that's quite a cry from 'Sony's online abilities are vapourware'.
I'll also add that it is possible for a company to overtake an experienced rival. It happens all the time. The easiest analogy is "You seem to think Sony can overcome 15 years of development and industry support Nintendo has had in a span of one console, I don't see it happening," but there's plenty of other examples in all industries. It's not like Sony have to start at year 0 with no knowhow at all and have to learn everything for themselves from scratch. They can take everything learnt from MS's Live work and developer feedback from those who have used Live and know what they want, and apply it with their own network services. That's 5 years of RnD ready to be built upon.
Exactly, people are talking about Sony as if they never overtook Nintendo and Sega 10 years ago "starting from zero" and became the uncontested dominator of the console market. As if Apple never resurrected themselves with that little thing called the iPod. There are so many examples.
Things happen all the time, and while i'm not saying Sony will come out with something that will make Live look like crap, it's defintely worth remembering what happened and expect what could happen.