This is an interesting one. Nimbuzz — one of the best mobile instant messenger clients I’ve ever used on my Nokia — are getting ultra serious. Nimbuzz let’s you use multiple IM and VoIP services (Google, Skype, MSN, Yahoo and the like) on the go.

They’ve locked in a potential 12 million new users through a deal announced today with StudiVZ, Germany’s largest social networking site.

Nimbuzz is now integrated directly into the site’s community facilities — meaning users can easily establish real time voice and text chat (not forgetting mobile file transfer!) communications with each other. It’s a win for StudiVZ, because they don’t have to go and develop their own ‘Facebook Chat’ style services — and it’s a huge win for Nimbuzz as they get access to a huge audience. It does make a lot of sense for both parties. Knowing how useful Nimbuzz is on-the-go, I wonder how many StudiVZ members will begin to make use of these new facilities.

Germany is well placed, from a mobile industry development viewpoint, to go nuts with this kind of thing. They’ve got a lot of high quality handsets in the hands of consumers — a good mobile-mature audience — and some decent data plan offerings.

If you haven’t tried out Nimbuzz recently, give it a go — www.nimbuzz.com.

I’ve got an interview scheduled with Geoff Casely, VP of Manfacturer Markets, Nimbuzz, next Friday — standby for more on soon!