Hey there,
I'm a CTI grad, and I'll give ya a lil taste of what I know or have gone through so far. I took the AT-SAT last spring and graduated last May '08. As already mentioned, you can't apply under the CTI announcement until after you graduate (and, of course, you get your school to recommend you). If I remember correctly, I actually received an email from either my school or the FAA (can't remember which) telling me when a CTI announcement was going to open up. Did the application and started the waiting game. (Btw, if you are CTI and apply for an OTS app, you still have to do the basic training @ OKC!!! You do not get to skip it...you can ONLY skip basic training if you apply under the CTI announcement! Also, CTI applicants tend to get processed faster right now...I'll explain later.)
I actually got an offer to Miami Ctr about a month after graduation, but turned it down (I have many reasons and won't go into them now). So I waited until October when I got my 2nd offer, this time for ZMP. I accepted and just finished up 2 days ago w/ my PEPC.
As far as AT-SAT scores and job placement (terminal vs en-route)...your score does not matter at all. This is what matters: if you picked a state (or states) with centers located in them, then there is a high probability that you will get assigned to a center. (And I know this because some FAA peeps came to my school last spring and told us this.) So if you absolutely, positively DO NOT want to work at a center, don't choose a state with a center in it.
Lastly, about CTI getting processed faster:
During the selection mtgs, applicants are chosen in the following order: first picks are current controllers transfering, second picks are military, third picks are CTI students, and forth picks are OTS.
Also, when it comes to getting a class date @ OKC, CTI students tend to get in faster (this isn't guaranteed!). This is because they have a certain # of seats for OTS and a certain # for CTI students @ OKC. Right now there are A LOT more OTS applicants than CTI applicants so their seats are getting filled quicker...which I noticed @ the PEPC. So most people I talked to were told to expect an OKC date around late March, April, or later. I was told to expect an OKC date around Feb.
So...that's what I have to say...sorry it's so long!!!