It comes pre-packaged and set up, with integration for the market (of questionable value) and Motorola emulators (fantastic - the more test targets the better).
Downloading Eclipse+ADT separately wasn't too hard last time I did it, but it's always nice to have steps removed. Most handset/java (Android, RIM, J2ME) developers I know have several Eclipse installations on their machine anyway to stop plugin conflicts so having one more is no big deal.
(EDIT: They have also removed Linux support, which seems to be an odd decision to say the least.)
They also have code snippets and Application Creation wizards. I think the later will be useful what with the api still being unstable(pmi pkg disappearing between 1.0 to 1.5 etc).