It get's hot for sure, but....

you could end up getting some really awesome room rates! Especially if you're flexible with your dates. I've lived in Vegas for 10 years now and can tell you that most people I know tend to hibernate from the heat when it reaches anything above 105. Yes it's a "dry heat" but most people don't want to walk the strip when it's that hot out so you may want to do your research and plan on spending some time doing fun indoor activities. The pools do help, but they do get very crowded and you may want to splurge for a cabana if that's your pleasure. Personally, I have very fair skin so I avoid the pools if I don't have a shady spot to lay.  
Bottom line, yes it's hot, but there's so much to do here (concerts, shows, fine dining, and fantastic shopping) that you might find it more enjoyable than you think.  
Just my thoughts!

XOXO
Bri

It is super hot in Vegas in August. Luckily the heat is less humid so you sweat less, but 105 degrees is what you should expect and you will just have to deal with it lol. You are going to be in the best city in the US in the summer...enjoy it!

Here's the average temps for Vegas. It's warm here and it can be a bit more humid because we tend to get more rain in the summer. Pools are a great way to stay cool when your outside.

High country of Colorado! 70 to 80 degrees 15% humidity, I do not even have air conditioning in my house, don’t need it. 300 days a year of blue sky. And you do not need bug spray either. I have a lake in front of my house in the mountains and do not own a can of spray. This is where AZ and TX and Oklahoma come to cool off.  West of the divide.
I think the word is getting out about the western slope. I am seeing more providers advertising around here this last year.

in August I recall some of the days being 120.It gets very hot out here in August not too many conventions here.
But you should get a good deal on room rates during this time.
If you like dry heat then come....put up some ads and enjoy your vacation.
I try to stay indoors air conditioning or at the pool but they can get very crowded.
This is just June and by 10am it is already in the 100s.
I have lived here for a little over ten years and I still am not used to the heat but I guess being from the SF Bay Area did not prepare me for the vegas heat even after all of this time.
Have fun