I've been working on a project lately that involves me reading a large amount of Internet Explorer resources.   I've been primarily using Firefox for over a year now.   My first motivator was the tab support, but the open code base and wide variety of extensions was the deal maker.   As I peruse the MSDN pages, I'm amazed at how much is available.   It really covers a lot of information.   Unfortunately, it's not geared for .NET development.   There's also a relatively high barrier to entry to write many of the extensions due to the COM interfaces.   I don't have a COM background, so it intimidates me!   It's probably not such a huge deal once you work with it, as with any language/platform, but with such a push toward .NET, it doesn't seem necessary to learn this.   Have any of my readers written IE extensions?   What was your experience?   What would have made it easier?