Unfortunately even after deleting the prefs and restarting, I still don't see any apps. I did successfully receive a transation though, so it's working.
Mt Gox is currently skewed significantly from every other rate. There is a library called Xchange which is what MultiBit uses. Alternatively BitPay export their blended rates:
https://bitpay.com/api/ratesIt'd be great to have some support for exchange rates in bitcoinj if anyone wants to contribute.
Regarding the rates, I can't see if this was discussed further. However I second the suggestion of using a different source for this information. I had a quick glance over the rates on the Bitpay page and they seem closer to the true market rates. Certainly for my local currency, NZD, the rate is much more accurate