Mac App Store (MAS) 64 bit submission rules?

What’s the status of Apple’s formal (or informal but enforced) rules for 64 bit-only submissions for OS X Apps to the Mac App Store

(Note: I’m not asking about iOS here, this question is for OS X apps).

Does it matter if it’s a new submission vs. an update?

As far as I know there are no requirements that applications in the MAS be 64-bit.

That’s correct. For now, there are no “rules” regarding Mac App Store & 64Bit support.

Thanks. Anyone know if they are still allowing UPDATES of Carbon apps too? (for a while, I believe they were allowing small bugfix-only carbon updates)