I'm a Pro user and got an email from them earlier this week telling me to migrate to the new free version.
At first I was upset too, and thought I bought the Pro app for no reason. But after upgrading to v5.0 I see that I'm still getting Pro features that Free users aren't getting (no ads, refresh all, and it looks like they even added "VIP Support" - email and toll-free #).
Seems that they just combined the 2 versions and opened up a new level of subscription level called "Gold". I'm not going to buy it but at least I don't feel ripped off since I'm still getting the features I originally paid for.
I agree with PossumPete - great app!