Judging by the size of the LED flash the main camera module does appear to be appear a little bigger than that found on the Lumia 920, but it does not quite match the size of the Nokia 808 PureView. This suggests an evolution of the Nokia Lumia 920's imaging capabilities, rather than a PureView 808 like generational step forward. The device shown in the teaser is in line with leaked images for a device named "Catwalk", which is likely to carry to the Nokia Lumia 925 index number.
While Nokia is likely to place an Nokia 808 PureView like camera module (i.e. 41 megapixel CMOS image sensor, at a 1/1.2" image sensor format) in a Windows Phone device at a future date, the likelihood is that the inherent hardware requirements mean this will not happen until the next generation of Nokia's Windows Phone hardware family comes on stream later this year.
The full details will no doubt emerge at tomorrow's Nokia event. All About Windows Phone will be reporting live from the event, so check back tomorrow, from 10am for more information.
Here's the full teaser video: