Glock has offered governments and government units a good deal: low prices and good trade-ins for their existing weapons. Glock has used MARKETING power to promote their brand and have done a good job of it.
I like Glocks. I also like Rugers, and recently picked up a used early SR9 (and added the Ghost trigger bar). For me, it seems to do everything the Glock does, at least as well, and it has a more natural grip angle for most folks. Does that mean I'll sell my Glocks? No. But the Ruger is a good gun, maybe great gun.
If Ruger ever starts to offer the kind of deals that Glock offers to police departments and militaries, we might see some change in the "balance of power" in the gun world. S&W is doing it's part to change that balance. (I also have a tuned S&W M&P Pro... nice gun.)