I came across this post on xda developers for configuring your Galaxy Tab for outbound and inbounds calls if you have verizon. It's essentially using VOIP integrated with some SIP service. I got it partially working. The step by step on the xda forum is missing some details but I am able to make outbound calls on my tablet now.
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I am troubleshooting the inbound call scenerio. It partially works...still trying to figure this out. So basically if I can get this working stable then I can forward my calls to my tablet if I am on the road through Google Voice. This will enable me to have complete functionality of my tablet.
We went to the lake today and I used google maps, Tunein radio and Mortplayer. It was awesome! If I can get this inbound/outbound call stable then its all good.