Well there would be a bit more to the XD evolution that a second safety.. which does actually address two of the major design concerns about the Glock (First being AD's from the trigger snagging on reholstering or the like, second being pure human perception and the concern over the lack of a manual safety or secondary and obvious - re: 1911 like and implimented - safety apparatus.

The grip angle I would actually submit as the more important evolution of any on the XD. The Ergonomics far exceed the Glock IMHO and are far more in line with the 1911 grip. This does actually address one of the more popular concerns regarding the Glock design.. 1911 folks really do espouse the ergonomic differences as one of the main reasons for not being overly thrilled with the Glock form factor.

But each shooter has their own preferences, I would just say that the XD is the rising star here. They've got several proven years already under the brand belt. I would think that if there were major design or functional issues that they would have already come to light considering the user base and general access to centralized communication about the weapon system via the internet. We live in a far different time than when Glock really started taking a bite into the pistol market.

I also agree that I don't see XD making 10mm .. then again I seriously doubt that you'll see a 10mm from Smith in the M&P line. As the name indicates it's Military and Police (granted that is more marketing than anything else) neither of those types of organizations utilize 10mm as a typical standard.

Where did someone get a chance to fondle the FN? Last I read it wasn't even out of proto-typing, but it's been a little bit since I checked.