M&P 45 mid size

Picked up my first gun today. Its a M&P 45 with a 4" barrel. I love the way it fits my hand, but I haven't gotten a chance to shoot it yet. Hopefully I can get that out of the way this weekend.

http://i17.photobucket.com/albums/b83/dontshakepandas/CIMG2217.jpg
http://i17.photobucket.com/albums/b83/dontshakepandas/CIMG2216.jpg
http://i17.photobucket.com/albums/b83/dontshakepandas/CIMG2220.jpg

Is this the 8+1-round .45 I've been hearing about?

Are there 3 sizes of M&P's?
standard,mid,compact?
I thought the 4" was the standard and the 3" was the compact.

I think that the 4 inch is as small as the 45 goes...9 and 40 hae a sub compact

The full size .45 has a 4.5" barrel. The mid size .45 has a 4" barrel and a full size grip that holds 10+1 rounds. The compact .45 that is due to release very soon has a 4" barrel and a shortened grip that holds 8+1 rounds.

The other calibers are a different story. The full size 9mm/40sw/357sig have a 4.25" barrel and full size grips and I believe the compact models have a 3.5" barrel with shortened grips.