Apparently it rarely happens, but there's another AA bonus for converting MR points to AA miles.

Details here. Effective dates of the promo Nov 5 through Dec 15 (has this been posted before? I haven't seen anything).

It's "only" 10%, but with a travel package, that's up to an additional 12,000 miles, which is not exactly chump change.

Edit: deleted the link. I'll try to get a link that you can get to from the website, unless it turn's out the thing is targetted.