As mentioned, use it and don't worry about it. Unplug from the A/C from time to time as well.
Thanks everybody for the kind replies.
Shall I in your opinion keep the rMBP plugged in or shall I use it with just the battery and change it when it is flat?
What do you recommend? Please advise.
According to Apple's latest info at that link, just use however you need to. If you need to be portable, run on battery. Otherwise, just leave it plugged in.
You don't want to intentionally run it all the way down to zero though if that is what you meant.
Thanks for the answer.
Yes, I meant that.
So it will not hurt if I leave it plugged in when I do not need it portable. Great!
Leave it plugged in whenever possible.
Battery good for 500 to 1,000 cycles - lookup Apple battery info for your model.
Cycling the battery every day will just use up the cycles.
I run the battery down to 0% a few times a year - full recharge and recalibrate battery.