I live just a block south of the rims just north of 24th st. west, and I get CBS (2.1), CW (2.2), NBC (8.1) and NBC's weather (8.2) in digital with a cheapo $10 indoor non-amplified antenna. No sign of digital ABC or Fox.
I also pick up analog ABC better on 25 than 6, and FOX better on 27 than 4. And actually neither of those come in very well, but analog PBS, and the analog CBS and NBC channels come in fine, much better than ABC or FOX. I assume an outdoor antenna would pull in ABC and FOX better, but it sounds like I wouldn't get digital anyway, so I'm not going to bother right now.