Tech news from around the web:

Google+ is now open to the public, the Los Angeles Times reports. After 12 weeks of field trials, the social network is still technically in a ‘beta stage’ however, with nine new features being added this week and more planned for the future.

Location-based app Foursquare has just clocked up a billion check-ins, says TechCrunch. On top of this, Foursquare has launched a new version of its mobile app for the iPhone and Android handsets. Read more

What would you pay for a fast-growing private internet company with hundreds of millions of active users and revenues of more than $500m?

If the name on the door is Facebook the answer, apparently, is: $6.5bn. That’s the valuation implied by the recent offer to Facebook employees from Digital Sky Technologies (the Russian investment firm also bought a chunk of preferred stock from Facebook that the company claimed valued it at $10bn, but that sounded like hype given that the benefits attached to those shares were not disclosed.)

So the $3.1bn $2.75bn valuation that has just been slapped on Skype sounds respectable – and is certainly more reasonable than the laughably low offers of $2bn or so that eBay was being encouraged to entertain earlier this year (curiously, eBay will not explain the difference between the $3.1bn value implied by its deal and the headline figure of $2.75bn that it claims for Skype). Read more