I have mixed views on tagging. On one hand, I agree that most information architecture forces the user to channel the content owner in order to find content; the inability to (easily) cross-reference data into multiple categories in most systems compounds this problem. At the same time, tagging doesn't innately solve this. With this in mind, Ignia has implented a different strategy for tagging that begins to address some of these limitations.
We've done quite a few SharePoint 2007 sites but a recent project required diving much deeper into the product, including extensive use of custom web parts, search indexes and registration on top of the standard arsenal of master pages, layouts, XSL style sheets, web part definitions, etc. Additionally, this was the first MOSS project for two of the project members which meant a steep learning curve for the team. This post discusses some of the lessons learned.