Oh what a lovely browser </sarcasm>. I admit I do use it for browsing the mobile web (i.e. site designed only for mobile browsers), it works well with those sites and I need one keypress less than Opera Mobile when paging through the mobile twitter site. However, if required to visit a traditional web site on my phone, I will use Opera Mobile. IE mobile’s rendering of traditional web pages is comical enough to almost win me a WebJam (and I did not have to dance).
The fun really starts when you try to build a site that works in both traditional web browsers and mobile browsers. IE mobile applies both screen and handheld stylesheets. Which can cause chaos. Even knowing this is not enough, I you try to counteract the screen stylesheet by removing styles in a handheld stylesheet, you need to do it properly.