I think this is just people taking that seekingalpha article to heart when it said commons might go as low as $1.85 and preferred may see 65% of par.
Until just a few minutes ago that meant preferred offered better return. Since hitting that magic $1.85 at least the downside for common is removed - and that same article said that in another scenario common might see $10. So at this point expect fannie to trade between $1.85 and $10.00 depending on which scenario seems more plausible from minute to minute.
In any case I think common should do you well if you bought in under $1.90.
This is a recco (as long as you are OK with maybe losing money)
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