RINOs are now defined as "anyone who goes outside the party line."
(it works on the other side too - Leiberman is a DINO to many, Zell Miller - well, old zell just went plain loopy)
Be pro-choice? Yer a RINO!
Voice reservations aboout Iraq? Yer a RINO!

From this feller's standpoint though, wouldn't a better definition be:
Someone who mistrusts big government.
Someone who wants to hold the government to be fiscally responsible.
Someone who believes in the role of international law (err, OK, that one is a stretch)
Someone who does not trust the government to unfairly intrude on other peoples lives.
Someone who supports the military when they come home.

But then that would make the majority of 'em RINOs.

to paraphrase (or rather wilfully misquote) someone else : This aint your father's Republican party any more.