ORIGINAL: Stamper
I used to use the wall charger overnight until I did some math on my chargers. It would take about 3 days charging to fully charge some of my 2100 mah batteries at the rate the wall charger charged. I use a Triton and other nicd/nimh chargers now and get a full charge. Look into your charge rate and your batteries capacity and figure out how many hours it should take to charge your battery. You might be surprised.
But that is only if you are charging back up from completely empty. This is usually not the case after a day of flying. You only have to put back what you take out.
So on the initial charge, then you need to charge it for the full time to get it full. But after that, you usually do not have to fill up the entire capacity of the battery because it is not completely dead.
Of course, a charger like the Triton or something like that is never a bad idea. One thing you can do is after a typical day of flying, take your battery home and discharge it using your charger. It will tell you how much you had left in the battery. Then using that number, you can figure out how long you need to put the battery on the wall wart charger after a typical day of flying. And always add an hour or two of charge time for safety.