That's not a bad thing - any Fallout is great, and more open world RPG shenanigans still add up to a good time - but it's been long enough. The follow-up, Fallout: New Vegas, is a little more recent, but with the same engine and similar gameplay, it felt more like an expansion pack than a true sequel.
Fallout 3 was one of the best games of the last generation, but it came out in 2008 - almost seven years ago. The people won't rest until they get Fallout 4, and with good reason.