Ok, it turns out that the iOS "task bar" does allow you to manually quit running apps. If you press and hold on an icon, they'll start to wiggle with a delete badge on them - like when removing or moving items in the springboard. If you click the badge, poof, the app goes away. I tested to make sure Squeezecast actually stopped playing music. I was under the impression that this action on the task bar would only remove the icon but leave the app running - I thought I recall Apple saying that app management was intelligent and happened automatically so you didn't have a manual task killer. Glad I was wrong.

Last night before going to bed I wiped all running tasks using SBSettings and this morning I woke up to a full battery meter. I'll try to test Squeezecast again tonight by starting a stream, stopping it and then putting the phone away for the night.