Figures, $10 did not sound realistic, when the alternative is priced at $499. I'm honestly just dumbfounded, how they have managed to set the entry price at this level. It leaves a giant opportunity for Sony to advertise their machine in a 'f2p'-esque manner that offers every basic feature for an initial investment of $399, allowing you to later buy different subscriptions for different levels of extra features e.g. ps+/gaikai.
Hope they haven't underestimated the effect of price and will proceed to surprise come late May. Of course, the loop-hole of advertising your product as 'starting from $299!' is extremely effective, and may provide them a solid counter-advantage.