Here’s our roundup of the week’s tech business news. First, the most popular stories we published in the last seven days:

Apple’s iPad 3G model gets off to a good start — It looks like opening weekend sales of Apple’s 3G version of the iPad were good. The new, 3G version of the tablet sold an estimated 300,000 units over the weekend, according to Gene Munster, an analyst at Piper Jaffray & Co.

Google acquires BumpTop: Will Android get a 3D facelift? — Google is acquiring BumpTop, a startup that aimed to improve the interface of your computer desktop. We speculate about what Google might do with the company — something related to the Android operating system seems likely.

How Wired.com tracked down the iPhone prototype finder — Wired.com’s Brian X. Chen wrote a blog post recounting how the site found Brian Hogan, the person who reportedly found an iPhone prototype in a bar and gave it to the blog Gizmodo in exchange for a $5,000 payment. Here’s our overview of the story.

Stock market snafu: Someone typed billion instead of million, says CNBC — Wall Street took a massive dive this week. A trade involving Procter & Gamble was mis-entered, as someone meaning to sell several million shares mistyped an order with Citigroup for several billion-with-a-b shares instead, sending the Dow Jones Industrial Average down nearly 1,000 points. At least, that’s the story being flogged by CNBC.

Tablets 2.0: Microsoft, HP probably building less powerful products — Microsoft and HP have reportedly canceled their existing tablet computer projects. Are they abandoning the tablet market to Apple? VentureBeat’s Paul Boutin argues that they’re not — instead, they’re giving up on the idea that a tablet computer has to contain the full power of a desktop or laptop computer in a much smaller, lighter device.

And here are five more stories we think are important, thought-provoking, or fun:

Why tech giants are putting the silicon back in Silicon Valley — When Apple bought chip design firm PA Semi in 2008, it seemed like a crazy move. Who’d want to go back to the days when giants like IBM did everything themselves, including making software, hardware and chips? Now Apple is starting to look crazy like a fox. And rivals like Google are following Apple’s lead.

Google Ventures plans to invest $100M this year, won’t fund evil — Google talked to journalists this week about its venture capital program. The big message: Now that it’s about a year old and has expanded the team from two to 11 partners, it’s ready to invest more money in more companies

Groupon CEO: Being in a band made my business rock — Groupon founder Andrew Mason lacks the stereotypical pedigree of a CEO running a tech company reportedly valued at more than $1 billion. Instead of majoring in computer science or heading to business school, he was a musician who somehow stumbled into software development. We caught up with Mason by phone to find out about how he made the transition, grew the company and where he might take it next.

Musk divorce case could hang over Tesla for up to a year — Tesla Motors CEO Elon Musk may have won an initial ruling in the divorce dispute with his now-separated wife, novelist Justine Musk, but the case is far from over, according to Mrs. Musk’s attorney.

Apple antitrust probe prompted by Adobe complaint, may lead to iPhone developer policy change — The FTC and the Department of Justice are reportedly readying an antitrust probe into Apple due to restrictive changes in its iPhone Developer Agreement. The probe was apparently sparked by a complaint from Adobe.

[second image via flickr/zabong]