Dont be discouraged if a starter prepared from a slant doesn't seem to take off quickly. When making a starter from a smack pack, I usually have strong activity within 6-12 hours and a noticeable increase in the amount of yeast cells on the bottom of my flask. When I prepare starters using the slants it may take 24-48 hours for the same level of activity, but you will get the same amount of yeast nonetheless. The starter I prepared at the meeting this saturday did not have any activity until monday morning, and when I stuck it in the fridge this morning to cold crash there was a nice thick layer of yeast at the bottom.
I just wanted to give those of you who do have slants a heads up, so that you are not discouraged that the yeast are dead and prematurely pitch your starter down the drain. And of course, always remember to give your starter a little sniff before actually pitching it into your wort. If it smells really bad, or "off", it is likely infected and you should consider saving your wort from a possible infection. Thats where a nice stock of dry yeast packets comes in handy.