The audience on the Mac App Store is not yet large enough to sustain low prices (like the iPhone can, sometimes) – it’s just not feasible. If companies keep selling software at bargain basement prices without a large enough market, it doesn’t end well – they go out of business and if that happens, the very people who love great apps lose too.
I understand the move, but it seems weird reading something like this on their blog just one week after their previous post about the "Changes for Clear", where they went the complete opposite direction on the App Store.
While app pricing, paid updates, etc. have been on a lot of sites lately, there still hasn't been a good solution for it. Let's hope that we see some changes soon, before some great companies can't support their development anymore.