Thats it, I've converted to Avalon

Automatic spell checking.

If you have a TextBox or a RichTextBox, set IsSpellCheckEnabled to true and VIOA: spell checking.

So that seals it. I'm converting to WinFX as soon as it comes out.

http://blogs.msdn.com/marcelolr/archive/2005/09/21/472407.aspx