A friend of mine tweeted this link last night. My favorite part about it? Read the very first comment following the post -- the one that succinctly points out the inevitable #6 on this list.
Rock My Car: 5 Things You Should Know Before Dating a Journalist/5.10.07
Given that this was written back in 2007 -- and considering how much the industry has changed since then -- you may as well tack one more on there:
#7. Be prepared to have to pay for everything.