Nokia (NYSE: NOK) has surprised us by unveiling details, specs, pictures and demo video of its forthcoming netbook device nearly two weeks ahead of its Nokia World conflab in Stuttgart. The 10-inch “Booklet 3G” is an attractive, well-specced machine that packs an integrated, hot-swappable SIM card slot.

Nokia has been describing its better consumer smartphones as multimedia computers for some time now. The Booklet, of course, is the closest it has ever got, but still carries over features from Nokia’s mobile heritage - a built-in assisted GPS receiver designed to work with an Ovi Maps gadget.

Indeed, services is a big play here. The Booklet carries an Ovi Suite app for accessing all the services including contacts, picture sharing, calendar, email and Nokia Music Store, also offering sync to a handset. It looks like something of a potential rival to any Android-based netbooks. Also, Nokia is wedded to Android’s mobile rival Symbian, which has no such desktop OS variant on the horizon; hence the strategic alliance with Microsoft (NSDQ: MSFT). This is the most innovation Nokia has gone for a while - but there’s less to get wrong inside an OEM PC running someone else’s OS.

The release materials claim an ambitious 12 hours battery life. Devices EVP Kai Oistamo in the release: “We will create something quite compelling. In doing so we will make the personal computer more social, more helpful and more personal.”

There are no details on carriers for this device; more expected during Nokia World on September 2. Networks have been using the subsidised handset model to tempt contract customers with netbooks for several months. With its existing mobile carrier relationships, Nokia may go in to the subsidised netbook game with an advantage.