The Code Analysis team at Microsoft has decided to include FXCop's spell checker in Visual Studio 2008.
FXCop was originally designed as an in-house tool used by Microsoft to ensure a level of consistency across all .NET APIs. As such, many of the rules it enforces cover usability issues such as publically visible identifiers. Among these is a spell checker for identifiers, a necessary precaution against releasing a misspelled method name that can never be changed.
The public release of FXCop was so well received that in Microsoft decided to include the FXCop engine in Visual Studio 2005 Team Edition. When they did so, some rules were added while others, such as the spell checker, were removed. With VS 2008 some of those "lost rules" are coming back.
In addition to the spell checker itself, VS 2008 will have limited IDE support for custom dictionaries. A custom dictionary, in the form of an XML file, can be added to an entire solution or be assigned to specific projects within a solution. Because the raw XML file is being exposed, all of the advanced spelling rules can be modified as well. David Kean has promised to cover some of these in a future blog post.