It's hard to tell wether it is strong or subtle. I just notice them clearly.
But it is not the shadows alone that bothers me. It's the composition of font and shadow - it just doesn't fit to the rest of the design. And to be honest, that ugly shiny color concept overall is a strain on the eyes. (is it "on the eyes" or "to the eyes"?)
I used to take my time to read as many posts as possible. But currently I can't stand it longer than 1 or 2 minutes.
It isn't very user friendly, at least not for dvi-connected LED displays.
I'd prefer much more contrast and darker colors. Readability and overview are the most important aspects for a forum, I'd say.