I would say your customers can sue you regardless of what you say in an email or blog post. Using lawyers to hide from your customers seems less than optimal.
I've seen that worry expressed several times, but have never heard about a case where it actually made a difference. Does anyone have a cite? It sounds like FUD spread by a lawyer to drum up more work.
Even though Sony didn't quite apologise, they tried to squash legal action through contract changes(?) and offering a free game download(?) as a form of settlement.