Maybe I've been out of the game too long, but $1/Mbps sounds very low. Last time I looked into it (one or two years ago) you could only get bargain bucket bandwidth approaching those prices, with fairly crumby providers.
Yeah, $1/Mbps sounds like a steal to me as well, which may be why it's a limited-time special offer.
thatamurgy's Pinboard links lead to this hosting provider: http://prgmr.com/san-jose-co-location.html
The machines in the original post being ~250W, they'd need the $362.50/month plan. But it's only at 10Mbps, which would only work if the application has low network requirements. Maciej appears to have gotten a much better deal, "For $206, I got 10U, 4 amps, and 100 Mbps connectivity", perhaps in exchange for promoting it through his blog. Everything's easier when you're a celebrity!
I'm assuming Amazon are a cut above that.