There are some limitations on Push notifications on an iPod Touch. When the iPod is awake and connected to wifi, Push Notifications will arrive almost immediately. But if the iPod is sleeping, it will only check for push notifications every 15 minutes. This means the push notifications will usually arrive too late for you to accept the call. You can get around this limitation by going to the iPod settings and setting auto lock to never, but this will of course drain your battery very quickly.
Note: The 4th Generation iPod touch allows a persistent wifi connection as long as at least one app has notifications on in the iPhone settings. This means the push notifications should come promptly on the 4th Generation iPod Touch. But also keep in mind that this will effect battery life.
keywords: iPod, Touch, acrobits, softphone, groundwire, push, notifications