Out of stock or close to it.

Ammunition in .223 or 5.56 calibers is getting harder to come by.

Scroll through these four pages at Wideners Reloading. Note what few .223/5.56 options are in stock. Note the prices on what is left.

As of this morning only Privi soft point is left at AIM Surplus.

AmmoToGo? FMJ choices seem mostly limited to off brands and surplus tracers.

Sportsman's Guide has some stuff on-hand in 5.56, but is also is taking back orders on other varieties with expected delivery dates in January, May or even October 2013. Ditto in the .223 category.   

In stock, but pricey premium options at SGAmmo. And plenty is out of stock.

Ammunition Depot still appears to have some inventory. As does Lucky Gunner. 

How many folks are planning to put an AR or a Mini-14 under the Christmas tree this year only to find it may take some real work to find ammo for it?

The inventories at these links will vary over time. My comments here are specific to published inventories as of December 1, 2012.