this a thousand times this. Nothing sucks worse than having to take back seat to Pet Npcs, Characters from the book or anything thats not a PC being awesome
I agree with you quite a bit, though I don't think it's always bad to have an NPC show up and save you. I mean, Dresden shows up and saves the day a lot, but he also ends up requiring saving a lot as well. So as long as you balance it out I think it works out, and can give the players a Brothers in Arms sort of feeling with the NPCs if they are always saving each other out of messy situations here and there. As long as it's not one sided. But yeah I totally agree, I want the players to get to feel awesome.
I mean how would your players feel in this sort of situation: Tell your players, "There's a man shooting fire at a bunch of ghouls and getting kicked around a block away, he looks in trouble." The players save the guy and he says, "Hell's bells, that was a close one. Thanks for the help guys, I thought I was a goner for a minute there. Name's Harry Dresden."
That's really how my friend described the Dresden novels to me anyway when they got me reading them. "Dresden gets beat up: The books."
Personally, my GM hasn't used any named characters from the novels yet.