Why does a .NET developer need or want BizTalk?

Somebody asked me the other day why he, as a .NET Developer, would be interested in BizTalk Server. 

If I only had one line with which to answer, I would tell my friend to invest an hour of time and watch the replay of Aaron Skonnard's webcast, "An XML Guru's Guide to BizTalk Server 2004". 

I met recently with the Spokane .NET Users Group and shared with them a lot of Aaron's thoughts that I had lifted and combined with some of mine into a presentation that I could give.  It seemed to go over very well, and it was clear that this is a powerful message.  I think that any .Net developer should take the time to watch Aaron's webcast and think about how their application development processes canbe shortened by bringing BizTalk into their architectural mix.  Especially in a SO architecture.