I'm another one that thinks everything in moderation. We actually love gaming in our family! That's not to say we allow it willy-nilly, but we definitely enjoy ourselves playing video games.
I really don't see games consoles as this force for "evil" that many parents seem to. Maybe that's because DH and I enjoy gaming and see it as simply another enjoyable activity amongst a whole host of other rather geeky and nerdy pass times we tend to share as a family (reading comic books, watching 80s fantasy films, visiting the Doctor Who Experience, playing Top Trumps, you get the idea)
We've had a Wii since DS was about 5, (he's 7), but DH and I got it for US (to play Zelda and Mario and re-live our teens!) with the added benefit that there are many child friendly games available. DS particularly likes the Lego Star Wars, Batman and Harry Potter games. There are many benefit to playing games like this, as part of a healthy diet of active, creative, age-appropriate activities (DS also loves making animations, playing violin, drawing, pottery and riding his scooter. He's not sporty, but likes the idea of joining a fencing club when he's old enough).
We have some house rules about TV, DVD, iPad, MacBook, and Wii use. DS has to ask to use them (we usually say yes, unless we have other plans, or it's too late in the day to start gaming/watching) An adult turns the TV on, operates the DVD player or the Wii (ie puts the discs in and takes him through menu set up), gets the iPad for him to use (it is not just left lying around); the MacBooks are mine and DH's so he must ask to use one, with supervision. We negotiate about how long he spends on the Wii.
I personally think that due to the Wii being a FAMILY possession, not DS's personal one; and the input from us that he needs to request to use it, DS does not have a sense of entitlement about playing video games. It is not his god given right to play video games, whenever he likes and for however long he wants. He needs to negotiate with us. 9 times out of 10 we say yes, when he asks, and he's usually cooperative about how long he plays.
I don't think (despite marketing) that personal, hand-held consoles like the DS or similar are actually age appropriate for children below teenage. I wouldn't buy one for my children until they are at least in secondary school. I just think it is important for parents to engage in their children's interactions with technology, which is very limited with a personal console; as well as this, a personal console creates a sense of entitlement in the child: "it's MY DS Mum! I can play it when I like!"
I don't do TVs in children's/teenager's rooms either. None of my siblings or I had one until we'd left home for uni. It's just not part of my upbringing and won't be part of my children's.