Source on google buying digg? Pretty sure this didn't happen. I just read that digg is worth 275M and they were looking for 300M before but couldn't get it.
The issue with Digg traffic is that it's completely untargeted, bounce rates are high, and you're basically back to where you started a few days later (particular if you write an article that is out of place from the rest of your site). The site in my sig takes a similar approach but the aim is for targeted traffic through natural click-throughs over an extended period of time.
I had one of my websites go to the front page of Digg end of last year before the voting system changed. Yes I go a boost in traffic and the server went down but the results wasn't mind blowing, it wasn't on the front page for that long though. I think its almost impossible for any new Digg user to get anything to the front page. You also need a site that is different, interesting or about any of those key points mentioned earlier: Apple etc. I think Diggs over rated though
shouts and a lot of loyal friends could place your stuff on the front page, but then we have to say that the diggers are not quality traffic, especially if you intend to make money off of them, because they won't stay on your page for a long period of time. They have a scanning and skimming behavior...