Jeffrey says Sharepoint is not a good development platform
Andrew and Sahil say
Sharepoint is not an easy development platform for newcomers and for one-off projects, it takes a few to get into the "Sharepoint Way", but allows integration with all sort of development tools (source control, testing, even Monad).
Sharepoint IS the best application platform around - especially for content(document) enabled applications (Gartner calls them CEVAs - content enabled vertical applications), with lots of pre-built funcionality and a huge number of APIs to be reused.
Sharepoint TDD (Test Driven Development)