The export or model is in a KMZ, DAE form. DAE is Collada and can be imported with
Poser under the Import in your top tab of
Poser or Pro. I think this was introduced when
Poser was 5. As for the models they are low Poly and not that great when in
Poser. If you want to convert these files simply bring the DAE file into
Poser and export as an Object or 3DS file if you like. To get the full version of this Google Sketch it will hold you back about $495.00 and I really don't think it is worth that kind of money. But for that buck it does export them as theses files.
3DS, DWG, DXF, FBX, OBJ, VRML, XSI
As for textures they are there but don't assign themselves well and again are very poor maps.
Also you will find this neat plug in but you will have to register to download. But it works with Sketch and converts these in to an Object file with the textures. Here is the link.
[Plugin] OBJexporter v1.6 20110402
http://forums.sketchucation.com/viewtopic.php?t=33448