incrediBILL - 2:59 am on Feb 4, 2013 (gmt 0)
Just thought I'd post it as a thread of it's own as it deserves attention.
Depending on whether you're validating a bot or blocking bad bots determines whether or not you should use "[NC]" to ignore the case.
For instance, when trying to validate Googlebot, the syntax "Googlebot [NC]" will also allow the bad fakes spoofing with "googlebot". In this case you would not want the "[NC]" used nor with any other major search engine or service being allowed to crawl.
When blocking bots and looking for any variation of a bad bot name is when you would use the case insensitive matching "[NC]" option to make sure you catch all variants. Using "Bad Bot [NC]" will match "bad bot", "BAD BOT", "BaD BoT" or any other mixed case combination.
Just an FYI to make sure you're using "[NC]" in the right places for the right reasons and don't inadvertently let the bad guys in the door with such a simple mistake.