Cabel Sasser:

Coda 2.5 is essentially complete. But, we’re still encountering sandboxing challenges. So, in the interest of finally getting Coda 2.5 out the door and in the hands of you, our very eager and patient customers, we’ve decided it’s time to move on—for now.

In short: Coda 2.5 will not be sandboxed, and therefore will not be available in the Mac App Store.

That’s unfortunate, but if it means a better product, then I say two-thumbs up. And Panic will be offering free crossover-upgrades to the 2.5 version for all MAS customers:

[W]hen Coda 2.5 is released, you’ll simply download Coda 2.5 directly from our website. It’ll locate your installed Mac App Store copy, and it will unlock. That’s it. You’ve transitioned. Free of charge.

I bought and recommended the Mac App Store version of Coda 2 when it first shipped two years ago because iCloud Sync was on the horizon and I very much wanted my sites in Coda and Diet Coda to sync with one another. But with Coda 2.5 being a non-Mac App Store app, it can’t support iCloud. But!… Panic is going to be rolling their own sync service. Nice.

Coda 2.5 and the Mac App Store