Ars has the news:
Google has a voracious appetite for parallel computing power, and that’s Peakstream’s business. My bet is that the company plans to use Peakstream’s software internally. I think it’s also possible that Peakstream will continue to operate and to make its middleware available to customers. So if I were Peakstream competitor RapidMind, I wouldn’t uncork the champagne just yet. RapidMind’s lives just got either a whole lot easier or a whole lot tougher.
More on Peakstream and Google (Ask News)
Peakstream’s site is down, but here’s a (Google) cache.