I don't think they actually type 'axe' but... from what I've seen, when people who say 'axe' for 'ask' type on forums it looks like this:
"OMG! Duz sum1 no wat type a bike teh rockhopper iz? I think itz specalized, but wat do i kno???!!!1 but it RAWKS!!!!1111"
*clutches head and tips over at the thought of regular mtb forums*