There is not a lot on the surface that has changed. As haus pointed out, Bluetooth paring now works similar to paring most other Bluetooth devices (like a headset) and you no longer have to have the phone and REDFLY connected over USB to do the initial BT pairing. Just press FN+F7 and the REDFLY will search for any BT device then you can initiate pairing with a 4-digit code. Once paired, you press only F7 as before to connect/disconnect over BT.
Also, if you go into Settings>System you'll (temporarily for now) see two versions of the REDFLY Settings app. One is the same old one you're used to. The other is a newer graphical interface version that's not fully functional yet. Eventually (sometime before it's out of beta), the driver will only include the graphical interface version instead of the old version.
While you may not notice many new features, under the hood this is a major update for us. We're moving from 1.4.0.xxx to 1.5.0.xxx. We're on build 156 of 1.5 so you can see we've been working on this for quite a while internally.
It's coded to be more stable, faster over USB, and enable support for new phones and features in the future. But it's still beta right now so you may see some issues.