It looks like to power a 5V arduino requires:
LiPo battery with JST connector: Lithium Ion Battery - 850mAh - PRT-13854 - SparkFun Electronics
5V DC to DC Step Up: 5V DC to DC Step Up - VPack PCB - PRT-08290 - SparkFun Electronics?
Charger: SparkFun LiPo Charger Basic - Mini-USB - PRT-10401 - SparkFun Electronics
The battery connects to the charger easy enough, connecting the Step Up boards seems very clumsy.
To connect the battery to the Step Up, a JST connector like has to be soldered to the Step Up board: JST Right-Angle Connector - Through-Hole 2-Pin - PRT-09749 - SparkFun Electronics
To connect the Step Up to the Arduino, requires soldering jumper cables to the Step Up board.
I guess this is no big deal, but thought this was fairly common and soldering would not be required.