PubMed® Redesign
NLM® is pleased to announce a redesign of the PubMed interface. While retaining the robust functionality, the interface was simplified to make it easier to use while promoting scientific discovery.
The changes to PubMed are outlined below. Please note that search processing, including Automatic Term Mapping, has not changed.
http://www.nlm.nih.gov/pubs/techbull/so09/so09_pm_redesign.html
Just saw this handy before/after chart: http://healthlinks.washington.edu/howto/pubmed_changes_2009/
New handouts too!
http://davidrothman.net/2009/10/06/new-pubmed-handouts-from-the-nnlm/