Just like Visual Studio, I find the context-sensitive help a big plus in the Powershell ISE. For example, let's say I want help on the Add-Type Cmdlet. I place the cursor on Add-Type in the editor, press F1, and up pops the info from the help file, complete with example code.
You should look into ISESteroids. I know this reply comes a little late. I have been using it for a year now. Very handy tool on top of TCC. Wish TCC would be able to pull in the whole ISE window. Now that would be awesome.