MacBook Pro: Should I put my battery out?

"Modern batteries are no longer affected by the ""memory effect"".

I personally leave my battery in, and the charger on.

If there are any sort of power cuts, you are protected.

The battery discharges and recharges a minimal amount of power and I wouldn't worry about it."

"There are a lot of different opinions here (I somehow guess it already).

I think this is also quite interesting which I found here (thx SidneySM for the link)

Several partial discharges with
frequent recharges are better for
lithium-ion than one deep one.
Recharging a partially charged
lithium-ion does not cause harm
because there is no memory. (In this
respect, lithium-ion differs from
nickel-based batteries.) Short battery
life in a laptop is mainly cause by
heat rather than charge / discharge
patterns.

I always assumed that full discharge/charge cycles are better than just discharging to 40% then recharging again etc..

So it's still quite inconclusive what will be ""best"" rather than laboratory conditions like storing it at 0° at a 40% charge level which of course doesn't hold in practice.

Summarizing the main points you mentioned...

The battery should be discharged to some level and possibly also be recharged without becoming fully empty
At least once per month a full discharge/recharge cycle should take place if this didn't happen already
Having the battery out will reduce clock speed
don't use the battery when there is no need (using the battery will of course lower it's life)

(I left the ""Apple doesn't recommend..."" out because I have the feeling they don't recommend it due to the potential power loss I'm of course aware of.)

I guess this really depends on preferences whether to take the battery out or not. The main important thing is to respect the 4 points above.
However, by having a look at the different sources you mentioned, it seems intuitive that taking the battery out when having your Mac running for a long time doing non-cpu intensive tasks will be good for your battery since it isn't exposed to the heat inside the notebook case. Taking the battery out for a too long time however at 100% charge won't be good either (see point 2 above).."