Warning for NaNo-ers using Google Docs

Google Docs (nee Writely) says I’ve written 1709 words. The NaNo site says 1664. OpenOffice.org says 1670. I ran into this last year when I uploaded my (just) 50,000 word novel to be verified by the NaNo site and found it was 800 words short. Just something to bear in mind. This may well already be on the official forums, but they’re down atm.