I trued it till it rolled straight from side to side and up and down. Then I took it out and flexed the spokes a bit, then set it back up to see if flexing it untrued it, it didn't, then I took the tension measure thingy, and checked the tension all the way around and it was pretty standard, averaging out to right in the middle that the little sheet I was using told me it should be at for the amount of spokes and the length of spokes.
If flexing it didn't throw off the true then you weren't stressing it correctly. Initially when you start stressing the wheel you will hear a lot of "pings" and the wheel will be significantly out of whack when you put it back in the stand. The degree to which you properly stress the wheel and it stays in true will affect how long it stays in true when you ride it.
Warning - you don't want to overstress the wheel - you can bust it up pretty bad if you do.
