I'd been looking forward to Dashboard in Mac OS X Tiger since Konfabulator always used to slow down or screw up my computer (maybe it was just my experience, though!), but Apple still has some work to do.
There's a huge delay for the widgets to load and display information, and it's not just when you first access Dashboard, either. Even when you're adding new widgets after Dashboard has loaded, or if you haven't accessed your widgets in a while, there'll be a significant delay to see them with new information. We're talking 5 seconds or so, on average. Why doesn't it do this updating in advance in the background?
Now that I've moved a bunch of stuff from my Mac's menu bar into Dashboard, I just wish it wasn't so slow to access. I'm very surprised and honestly a little disappointed that this feature left Apple's HQ in this state. But, perhaps there will be an update to it soon!