Lily?

[heather the buzzard]

No: HPFGUIDX 131765

I just read this quote from JKR, which I hadn't personally read before:

Now, the - the important thing about Harry's mother - the really, really 
significant thing - you're going to find out in two - in two parts. 
You'll find out a lot more about her in book five, or you'll find out 
something very significant about her in book five, and you'll find out 
something incredibly important about her in book seven.

I presume that this quote is the origin of the question "What is Lily's 
Big Secret?" 

But, it left me wondering -- what "very significant" thing did we learn 
about her in book 5?  The only thing I really recall was that DD spelled 
out in more detail the 'old magic' her sacrifice left in Harry.  But 
that's not really telling us anything *about her*.  Other things, like 
that she belonged to the Order and had 'thrice defied' LV, also apply to 
James, and to others as well in fact.  And they're not really all that 
*surprising* things heh.

Am I forgetting something, or did JKR change tack along the way?

heather the buzzard