What really puzzles me is that this month's Animeland (basically the most popular French anime & manga magazine) actually announced that
a second season of Full Metal Alchemist was in the works, and the information seems to correspond with that leak since they even mentioned that the series would get a new director (even though they didn't clearly name Yasuhiro Irie).
I didn't pay much attention when I read the article, as I don't tend to trust French sources anymore when they're not backed up by trustworthy Japanese ones... but could they actually have obtained the information before everyone else? That'd be a first.
In any case, this could very well be the best way to boost the ratings for TBS's Nichigo. Of course nothing guarantees the series'll air there (if there's a new series), but I reckon it makes sense to beg for a new season to promote the newly-created timeslot, since it worked wonderfully back in the Doroku days.