I'm another one who rarely if ever shuts down the laptop, and I'm on my 4th laptop Mac now (nothing wrong with any of the ones I had, in fact, they're all still being used, I just moved onto newer models).
On just about all of them, all I ever did was closed the lid and let them sleep. Which is wonderful because it means that whatever you were doing, even if it was started last night, you open up the laptop and you can go right back to where you left off. The only time I'd shut my laptops down beyond re-starting after an update is if they were going to be unplugged for a long time and I don't want to drain the battery, if they were going to be left untouched for a several days (rare, as I'm almost never without my laptop; it gets opened and worked on at least once a day), or if I was going through airport security.
This last was my own paranoia. I just wanted to make sure the laptop was going to stay as safe and secure as I could make it as it was removed from its bag, put in a bin, x-rayed, put back, shoved under a seat and such.