One of the great and amazing discoveries of wikipedia is that while
there are a few jerks out there of course, the general population of
the Internet as a whole is not filled with rabid savages looking to
wreck websites.
Brion blocks abusive bots from time to time, but it's not often a big
problem. I'd say for a smaller site just starting out, there's almost
no chance of a bot doing anything.
--Jimbo