I discovered something that is really great when the Touchpad and the Pre3 are linked via bluetooth. Once these two devices are linked, you can connect other bluetooth devices to these devices and they all work, simultaneously.
Let me site an example: I was talking on the phone with my Pre3 using a bluetooth headset. While on the phone, I received a test message from someone. The test message not only went to my phone but it also went to my Touchpad. I was able to receive and send text messages using my Touchpad even though my phone's bluetooth was active with my bluetooth headset.
I did not realize that a device could function with two other devices simultaneously with bluetooth until now. This makes the ability to connect my phone and tablet together more valuable in that it does not limit my ability to use my bluetooth headset at the same time. This is a really great asset in having the Pre3 with a Touchpad.