Also, for most decor items (and pretty much all wearables), you can use a box for the physics mesh instead of trying to calculate the physics. Unless you get upwards of 5000+ polys, you will upload almost instantly. If your item has a specific physics shape, taking the time to make a simpler physics mesh will not only save upload time, it will also make your item more efficient once it is inworld.
PS. I know Yoyo knows this, but I added this for anyone searching on this subject.
Building using prims, sculpties and meshes. Texture creation techniques.