I've got a WD TV Live Hub with firmware 3.03.13. An iPod Touch and an iPad2 both with iOS 5.1. And a Android 4.0.3 tablet.
On all three devices I can play media from the hub's hdd. I can control the hub from the remote tab in the browser interface. So no connectivity problems
But neither iDevice ever detected the Live Hub from de WD Remote App. I tried reinstalling the Apps. Restoring factory defaults on the Live Hub. Nothing seems to work.
On the Android Tablet it worked for about 30 seconds, but then connection was lost. Restarting both the tablet and the Hub, reinstalling the App, nothing works.
So add this to your long list of bugs WD! Try fixing old stuff befor adding new buggy stuff.