They key for me is that I have to have a device I can use to RDP back to work in case something needs fixing during the day. It doesn't happen very often, but I have had to duck out of a session before to fix something back home. I brought my Surface Pro with me to MMS this week and it worked out great aside from the battery life. I was able to get a charge at some point during the day, so I was never completely dead. If MetroTwit wasn't such a dog on RT, I'd bring that instead.
If all someone has is a traditional laptop, I'd definitely leave that at the hotel. Just not worth lugging around.