By now every developer who cares about memleaks in AS3 knows not to use anonymous functions inside event handlers. Callbacks should have a name (so they can be GC'd) and weak references should be used. However, weak references won't totally save the day here. In AS3, asynchronous objects register themselves with the Flash player when they run. If one of those objects (Timer, Loader, File, DB transaction) continues to be referenced by the player, it's essentially unreachable to you.
[assertTrue( ): Garbage collection 2.0 vs. Web 3.0](http://asserttrue.blogspot.com/2009/09/garbage-collection-20-vs-web-30.html )
