Microsoft's collaboration and portal product is quite different from the other portal offerings. Microsoft "Developer Evangelist" Sebastian Weber provides a nicely detailed and of course quite positive introduction to SharePoint, where you can learn about architecture, web parts (portlets in Redmond-speak) and much more. He also describes what comes natively with the product and writes that "technicians tend to forget that SharePoint is ready to run out-of-the-box." Indeed, we've seen many a developer get into trouble customizing SharePoint, though it's not necessarily their fault. While Sebastian also touches on some of SharePoint's weaknesses, unfortunately he does not shed any new light on the upcoming new release, which is going to be a major upgrade challenge for existing licensees.