I was in the Army when they switched from the 1911 to the Beretta. Having spent a lot of time on both platforms, I never cared for the Beretta as much. It's a good gun, but it just never felt quite "Right" in my hands. On the contrary, I bought my wife an XD subcompact, and after shooting hers, I was so impressed by the weapon that instead of buying one of the other 3 or 4 pistols I had narrowed my choice down to after a year of research and shooting, I bought the XD for myself.
I have not had the chance to handle either the A2 or the Mod 2, but based on the changes from previous versions of each, The Beretta doesn't seem to have changed much except for the internal frame buffer, time will tell if that's a big deal or not, but rounding the trigger guard seems like a step backward to me, particularly if the guard wasn't increased in size to handle gloves. The XD didn't change much to the Mod 2, (Which is a good thing, hard to improve on the platform). The updated factory sights are probably the best new feature on the Mod 2.
I was one of those guys who didn't want an XD, I wanted a 1911 or an S&W M&P, but once I shot that XD, I changed my mind.
Now take that with a grain of salt, I love the XD Sub compact (With a pinky extension it fits my hand perfectly and I have big paws), I didn't care for the grip on the full sized XD quite as much as the subcompact, but I had no complaints either.
I don't think you can go wrong with either, but my preference definitely sits with XD platform.