Don't know if anyone has posted the particulars yet on the P-3AT, but here they are:
Length: 5.16"
Height: 3.52"
Width: .75"
Weight: 7.3 oz. [unloaded]
Barrel: 2.76"
Capacity: 6+1 rounds of .380 ACP [Kurz]
The frame size and weight are between the P-32 and the P-11. Production and shipping should start in May, per Kel-Tec...