The nominal voltage of one cell is 3.6 V so a 2 cell pack should be 7.2 V. Once charged, the cells will be at approx. 8.4 V but under load that voltage will soon decrease towards the nominal value.
From a voltage point of view it seems to me that your batteries are O.K.

I usually test the capacity of new batteries by discharging them over a known load in order to make sure they are allright before putting them into an aircraft. Voltage measurements alone will not tell the whole story.

You will find some practical advice on Li-Ion batteries here: [link=http://www.troybuiltmodels.com/LiIonBatteries.htm]http://www.troybuiltmodels.com/LiIonBatteries.htm[/link]

/Red B.