take a look at some concepts of developing web parts in asp.net 2 (whidbey):
thanks to RobertK (he seems to find the good stuff lately), i was pointed to this tool:
it seems like a cool little utility to get quick, concise information about your sharepoint environment in a one-stop shop place. it isn't web-based and i haven't done much testing around on it, but it does a good job giving you a snapshot.
since there isn't any screenshots on the site (you can download a free trial), i'm including one here (blacked out areas are there to protect the innocent ;-)).
so if you haven't been paying much attention to whidbey (.net v2) lately, and you are a sharepoint developer, you may want to start taking a look.
whidbey will introduce the web part framework (called portal framework in whidbey for now) with .net v2. all the skills you've learned as a web part developer will help you understand the development in whidbey...so you'll have an immediate head start already.
nikhil kothari (a member of the .net team) had a great post today about cross connections on web parts in .net v2. Read it here: http://www.nikhilk.net/Entry.aspx?id=53
some new articles just made available on msdn office developer center on branding sharepoint...helpful information in assessing customization, the wheres, hows and impacts of doing some of the customization: