I dunno about you but I don't like to travel with large bodies... so if I'd be you I'd take D5100 + 28-75/2.8 + 35/1.8 for really low light and I'd take too 18-55 just for the situations when I will need something wide. This is a light enough setup. I hope your Tamron does have AF motor...
This isn't one of those "What should I bring with me to 'xxxxx' " questions (I hate them too :P)
Yeah it is. But that's OK
I've been there a bunch. I'd recommend the D3 and the 18-55 Nikon OR the 28-75/2.8 Tamron AND the 70-200/2.8 Nikon VR I. That gives you a decent range, 18 or 28 to 200mm. Get a belt pouch or small bag in place of your back pack for the lens you are not using at the time and fire away.
Lots of interesting architecture in Vegas. I'd definitely take the 20 for that. Probably the 28-75 also just for the flexibility of the zoom. Otherwise, I'd probably take the 20 and the 85 with the D3 and call it a day.
Only if you want everyone to see you lugging it . Settle for a Kimber 1911 and get best of both worlds. Any of you have the I SHOOT AUTO t-shirt? Its for photography, but I wear it to the shooting range sometimes just to give the buddies a good laugh lol.
Going on March 11 everyone tells me I don't need a telephoto
Side trips to Zion and a colorado raft trip
I would choose your D3 and 28-75 and leave the rest at home
I will be taking d700 25-50 f4 ais, 28 2.8 ais and a 135 2.8 ais