I've been a FF user for a number of years. The new edition - FF3.5 - is out and I notice a substantial increase in speed and a bit more features. Yes it has a private surf mode. If you already use FF go get the update. If you've never used FF, I recommend it to anyone who wants a user friendly browser. (Note that some addon's my not yet have versions for 3.5)
LINK
TSF has a forum dedicated to FF so your questions can be answered there.
LINK to FF Forum
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