Well, first from the Macbook, anyhow. ;-)
Leopard installed very simply, and now I'm moving slowly along the Dock checking stuff out.
Dashboard was a good place to start, in fact, since it reassured me to poke about to figure out how things work.
First main application to configure was Mail.app. I expect to end up in Entourage soon enough, but I was interested in checking out the built-in tool set first. It took me a minute or two to configure, because despite being the mail admin I wasn't quite sure how my internal SMTP server is set up for authentication, etc. However, it now works fine, sending and receiving mail happily.
Safari I'm familiar with from the Windows version. It's fast, and it does the basic job of showing web pages well. I'd like more tab features - a way to have tabs show all the time, for example. I can of course just go get Firefox, but again, I'd like to give the built-in tools a chance.
I've not really got anyone to iChat with, so that's gone back into the Applications folder.
iWork and iLife are for another post!
iCal is going to be a possible issue, since there is no built-in way to connect it to Exchange. This will need some thought, but of course I have my Blackberry for calendar, so there is no urgency.
Photo Booth is as silly as anyone could hope for.
I'm going to hold off on Time Machine until I have all my data transfered from my Dell.