Having just installed this new version on my laptop, I chose to install the firmware for my Broadcom B43 wifi nic. The install seemed to go well and fwcutter was downloaded and the firmware extracted. I clicked ok to complete the process and the whole laptop froze. Even the mouse pointer stopped. The caps and scroll lock keys didn't respond, nor did the power button and there was no console access. I had to hard reset the laptop in the end.
Upon restarting, my wifi card was enabled and working. I set the ESSID for my lan and the dialog box showed "Generating PSK" with the wifi light flashing on and off every so often. After 40 minutes of this I clicked cancel. The process seemed to stop, but the process bar continued to display "Connecting" and now the cancel button was greyed out. So, I clicked "quit" instead. The taskbar icon for the network app still showed "Connecting to" when I hovered my mouse over it, but wouldn't respond to clicks.
So, I then opened the "Network Settings" app in the "System" menu. I set up my wifi connection in this app with my ESSID. This accepted the settings, but didn't seem to make any difference.
In the end, I decided something had probably crashed in the background and rebooted.
After logging in again after the reboot, I clicked on the network icon in the taskbar again and disabled the wired nic. I then clicked "Connect" on the wireless and it worked perfectly, connecting immediately. I still have no clue what died or why, but it works now, so I'm not losing any sleep over it.
This isn't meant to be a techy explanation, but I do hope that if someone else encounters similar problems that the steps I took might help a little