I started shooting Glocks about 5 years ago. I have a G17 first gen that I use in 3 gun matches. I won an XD40 last year at one match. I tried it out, and it is sweet. There are 3 issues that I have with the XD:
(1) The grip angle is great, just the same as a 1911. But, it is different than the Glock, and I am training for speed with accuracy. I want to stay with one style of pistol.
(2) The XD seamed to be "top heavy" compared to the G17. I think the Glock is more streamline than the XD, and thus I percieve the weight of the G17 to be lower.
(3) I really don't want another caliber to contend with. If the pistol I won was a 9mm, I would have done just what I ultimately did.
I traded the XD for a G19 3rd gen. Since then I have added another G19 2nd gen to the arsenal.
I think the XD is the BEST value for someone getting into a new handgun. It comes with features and extras that no other manufacturer offer. I have suggested my soldier son and son-in-law both consider a version of the XD for their next pistol purchase, as niether one are too excited about the Glock. (Just a footnote, all 3 Glocks are equipped with XS 24/7 Big Dot Sights.)
kdubya, the great thing is that you ultimate choice of either the Glock or an XD9 will be a great one!