Krazy...The batteries are a seperate component of the notebook. THe problem is within the battery component itself & has no effect on the system at all...Well unless the system actually blows up that is

...As far as "not checking" ...While I am sure Dell & Sony performed hundreds of tests there is no way to make sure everything is perfectly safe. The open marketplace is the real testbed, as the components are tested by the millions in every concievable enviroment & situation. It is unfortunate that this recall occured for Dell & Sony. The thing you have to take into consideration is the fact that there are millions of batteries out there & only a few hundred have had issues.
In the interest of safety they are recalling the entire productin lines to ensure that there are no more issues.