How Often Can MBP Be Put To Sleep?

I never shut mine down unless I need to do a software update. Won't hurt it at all. I've found that letting it sleep overnight will use 4 or 5% of the battery. That said, when not in use you should plug it in whenever you can. As an example, I use mine on the train for about an hour, plug in at work for the day. Another hour on the train ride home, and maybe a few hours use after dinner. Then it goes back on the charger overnight.

You can sleep the machine as many times as you wish. The only time I ever shut mine down completely is if I am travelling with it on a prolonged trip, or leaving it behind for several days. Otherwise it is alwasy on 24/7 (has been since I got it in March 2009) and every evening it goes to sleep after 3hrs. In the morning when I leave for work I just log off and then close the lid to sleep it.

My 3yr old battery (don't know how many cycles on it now, over 300 I'm sure) will drain from fully charged to about 86%-87% after 10 hours or so in sleep.

Shutting down is supposedly more stressful to the hardware than sleep, and there's really no practical limit to how often you can put it to sleep. I probably close and open my MBP several dozen times per day, on average. It makes me worry a little about the hinge, but I haven't had hinge problems since my old PowerBook G3 more than a decade ago. (And to be fair, I kind of whacked the hinge kind of hard on that machine, which probably played a role. 😊)

As for the battery, if you leave the machine sleeping and not plugged in, there is a slight drain over time, but it's not significant unless you leave it that way for a long time - like, for example, if you leave it sleeping with no power cord connected overnight.

An overnight sleep for me does at least 15-20%...