Why are Desktop,Places,Applications so slow in Gnome Panel?

[Jim Christiansen]

I have noticed on a bunch of computers that my Gnome panel is really slow (5 
seconds or so after a click) to respond to clicking Desktop, Places or the 
Applications buttons- the first time after logon.  They respond a little 
better, or normally, afterwards to repeated clicks.

These computers are all newer high-end single or dual 64 bit, 1 to 6 gig ram 
systems...  All clean and up to date FC4.

Any ideas?  Thanks,  Jim