MacBook – Will not using battery in MacBook make it last longer

Yes their design limit is to exceed 1,000 full charge cycles. Quoting from Apple on batteries:

The built-in battery of your MacBook, MacBook Pro or MacBook Air is designed to deliver up to 1000 full charge and discharge cycles before it reaches 80 percent of its original capacity.

I have been bowled over at how well the internal battery chemistry holds up over time. Of course, bad batteries fail prematurely all the time and need to be swapped, but my gut feel is way more of these "go the distance" than all the older removable batteries.

http://www.jinx.de/SmartSleep.html will let you control it via GUI. The app is $6 on his website or $4 on the Mac App Store.

(Note: I have no idea how this app ever got approved for the Mac App Store, but it appears that Apple is stone-walling the developer on approving a Lion-compatible update. This seems to be Apple's passive-aggressive way of getting apps out of the Mac App Store after they were approved: they don't want to upset people by yanking the app, so they just won't approve an update and eventually it either breaks and the developer pulls the app because they are getting so many support requests, or people just stop buying it. When the sandboxing rules hit in November, we may see apps start disappearing from the Mac App Store. All of which is to say that if I was going to buy this app, I'd buy it through his website even though it's $2 more. There's a demo available, although the "request a trial" button didn't work for me, I assume it's a temporary glitch that the developer can fix. It also appears that Mac App Store customers can download the version from his website and use that, so if those $2 are really important to you, I guess you could try that.)

If you'd rather spend time than money, http://tidbits.com/article/9115 has a script that might help.