I just switched to toodledo from my previous application and I'm quite impressed to see all this app manages ! Just was a bit disappointed to see, although it handles tasks like a charm, notebooks aren't synced correctly to iDevices.
Try to create a new notebook page (whether online or in the iApp). Then modify it online. Afterwards, open toodledo app on the iPhone, sync it. You'll see that all tasks are in sync, but your last modification to the notebook page will only be reflected after a forcefull sync (available in the options of the toodledo app on iPhone).