It is obvious that bluetooth isn't as fast as hardwire usb tethering, but I have used the tether software, tetherberry thru bluetooth and it is/was quite a bit faster, so the slowness cannot be blamed on bluetooth data rates. So what is it? I use a torch on ATT.
the bridge and tethering are two different things. The bridge browser is just bridging to your phones browser. If you tether you actually use broadband browsing on the Playbook browser.