The other answers I could think of.
The XD grip fits my hand better than the Glock.
The XD uses steel mags instead of plastic.
The XD take-down is simpler.
XDs are a little more affordable too.
Being a 1911 guy, I like the idea of the grip safety, but think the execution in the XD could've been done better.
“Fits my hand better” is about the only compelling argument I see, and that’s a matter of personal taste over alleged obselesence.
Don’t get me wrong, I think the XD is a fine tool if you prefer it. I just get antsy when someone bashes the Glock as “obsolete” when it is only marginally different from the latest-and-greatest. (And yes, if someone CAN show me a downright superior tool, I certainly want to know about it.)