40D shutter button vs. 50D

I have not been using my 40D for a few months now (my wife thinks its hers) But I picked up the 40D the other day to take a few shots and the shutter button felt not as firm or responsive as the 50D . I don't know if its always been like that or maybe the shutter button is getting bad. If anyone has these two cameras could you please check to see if you feel much of a difference between the two shutter buttons. If the button on the 40D is getting bad I know it could probably keep going for a long time or crap out tomorrow. I'm just kind of curious if it could be a problem or not.

Anyone?

Could it be just wear? The 30D I bought used has an obviously worn shutter button. It works fine but it doesn't have the response of a new shutter. Oddly enough, on my 350D, the shutter button decided to get super sensitive before I sold it. You can't expect tens of thousands of clicks without any effect.

The shutter button very rarely goes bad.