For 1948s, the second "A" normally points to a denticle. If it points between two, then it's an "Off Denticle" penny. The Coins & Canada page has example pictures of both. There's a scarcer small-dentical variety, but that Website doesn't have an explicit picture for it. The two are compared in shots near the end of this thread.
For 1949, the normality was reversed - in a big way. Almost all '49s are off-denticle. An A-to-denticle '49 is rare. It goes for twenty bucks for a Fine.
Feast your eyes on this one:
This expanded money shot shows that it's a 1949 A to denticle. You'll have to scroll it, but you'll see how the A points to a denticle:
Man, did I luck out! This one's elbowed out a 1940 Newfie as the most valuable coin I've found.
And to think I found it through copper penny hoarding
![Very Happy :D](./images/smilies/icon_e_biggrin.gif)