There is no battery charging issue, as weird as this may sound.
The new battery has almost double of the capacity of the iPad 2 battery.
Unfortunately, the charger is still the same, charging the larger new iPad battery much slower.
Charging takes almost 1 hour for a 10% charge, which is quite slow and...annoying.
There is no way Apple can actually shorten the charging time since the 10W charger simply isn't capable of charging the new iPad faster. Only solution I can see: A quick charger.
Unfortunately, I think that a quick charger isn't compatible with the new and larger battery, which may need to be charged slowly to be on the safe side (for durability reasons).
Yes, the biggest flaw of the new iPad is actually the charging process. Not only does it take almost one single hour for a 10 % increase in battery capacity (actually the overall charging period from 0% to 100% is close to over 8 hours) but what is worse, the battery capacity even drops when you play a game while the iPad is charging. At 100% display brightness, playing AirSupremacy, battery capacity drops by 2% or so...every 10 minutes. Ouch.
The new iPad is a great tablet, the Retina display is absolutely amazing but Apple urgently needs to address the slow charging process. I would even pay up to 100 bucks for a quick charger, no kidding. The slow charging process is the most annoying thing I ever encounted on an Apple device. Honestly.
I don't know what Apple was thinking...over 8 hours for a full charge are at least 4 hours too long.
The fact that the new iPad charger can't even cope with power consumption during extensive usage, is kind of sad.