Not at all. Still playing in multiple home D&D games, SW games, Living Greyhawk, etc.
The last non-d20 game I played in was a session of TORG (blast from the past) last fall, that went so smashingly poorly that we won't be trying it again.
I feel, for the most part, my players are familiar enough with the d20 ruleset now that we rarely get into game-mechanics questions anymore...so, the rules rarely get in our way now.
What I *am* seeing us do more of is variants...a D&D variant based on Pern, a SW variant based on Firefly, etc. But, that has little to do with the mechanics, and more to do with changing up the settings.