Where should we be submitting feedback about weirdness with how the mac client is updating addons? The "Report a Bug" page that the client pops up?
FYI: I've just started testing it out, and noticed a problem with the fourth addon I attempted to update. It rolled my addon back to a previous version. I checked out the curse page for it (BankItems: http://wow.curse.com/downloads/wow-addons/details/bank-items.aspx?PageIndex=1) and the "Current Version" line at the top of the page doesn't agree with the list of updates listed further down the page. It makes me suspect that the problem might be on the Curse side of things rather than the client.
Edit: turns out the client (and curse) are ignoring files tagged as "beta".