This blog has moved to http://blogs.msdn.com/b/appfabric please update your links!
Lately on http://endpoint.tv we have been doing a series called WF4 Activities Best Practices with Leon Welicki. Many of you wrote in asking for the sample code so I’ve published on MSDN Code Gallery - WF4 Activity Best Practices Sample.
Be sure to check out these episodes – great advice on authoring activities. Not all of these have published yet I’ll update with the links when they go live.