Dr Chimps must be referring to Fear and Loathing in Las Vegas. Great book, great movie. Quotes from the book on the internet somewhere, worth the effort to look them up.
Crowds & summer time go together. Weekends or during the week, not much of a difference. Around Christmas & New Years , for me, is the best time. Super Bowl time is party time 24/7. Girl friends are nice, but it is Vegas after all. Sex, sex, and more sex everywhere. And everyone seems to want to hook up, from the weekend party girls from LA to the local stuff. 10, or near 10, girls everywhere. Might find that the K you plan on dropping at the tables is not nearly enough.
Try booking rooms by going on line and looking up Vegas packages a month or so before planning to go. Prices are always changing. Vegas needs the tourist bucks and the summer rates should drop even more, because the economy is only going to get worse. The Red Rock, outside of Vegas if you want to avoid the major crowds, is cool. Planet Hollywood and Hard Rock are both extra cool. Check the pools out for some unreal hot chicks. Including some exceptional well kept cougars.