Please forgive this leisure plat for starting another denied/lost upgrade thread (I've seen enough of them posted in my brief time here), and please doubly forgive me if a similar story has been told previously (it may very well have). Since many mistakes must have coincided in causing my predicament today, if you are unable to offer advice, you may at the very least find my story interesting.

So I was a passenger on CO1753 IAH-SJU this afternoon/evening (12/15). The Sequence of events is as follows:

-Booked my V-fare ticket back in September and immediately assigned myself an exit row aisle seat.
-At the 5 day mark, when I wasn’t EUA’d and noticed there were only a couple of F class seats left (at least according co.com’s offer to buy up to F class, there were only a few seats left), in a last ditch effort to push myself to the front of the pack, I waitlisted for a mileage upgrade.
-I check in at the 24-hr mark. Still no upgrade, and I start to regret requesting a mileage upgrade in the first place, since there end up being only 3 elites on the standby list and I’d probably have been at the top anyway. None of this is very important, though.
-I arrive at the airport 3 hours early and monitor things from the PC: F class checked in full, but I’m at the top of the upgrade list. The entire flight is COMPLETELY FULL, and they are offering $300 vouchers for volunteers (at the kiosk).
-I get to the gate, I board with the elites (actually, I am the only one) and take my coveted 737-900 exit row aisle seat (16C) in an empty cabin.
-30 min later, right after the last boarding zone or row range has been called, I am approached by a man who angrily shows me his boarding pass. He’s in 16C too. I show him my 16C BP and say, “Don’t worry; we’ll resolve this”. We call an FA over, and she says, “I’ll go check on it.” I figure I’ve probably been upgraded, though I’ve seen stranger things with seat duplications. The FA goes to the back to call up front and returns 2 minutes later: “Mr OilOwl13, we’ve got a seat up front for you.” I gather my things and say, “Could you let me know which seat?” She says, “There’s only one. Just take your stuff up front.”
-Of course, the duplicate boarding pass man takes my orig seat, I take my stuff up front and identify myself to the front FA. All seats in F are occupied. She says, “Wait here”, so I sit there holding my luggage for a couple of minutes while everyone in the Y cabin takes their seats and the crew prepares to close the door.
-She comes back and says unapologetically, “There’s been a misunderstanding. You’ll have to take any open seat” (she motions towards the back of the plane). WOW.
-The door is now closed, and the last few ppl are taking seats after stowing their luggage. I make my way back, and I explain what happened in 5 words or so to the FA that had originally informed me I was upgraded; she is quite apologetic, and says, “That’s just not fair to you.” She finds me a seat; there’s only one open (it’s back in row 25/26 – a window; at least it wasn’t a middle). So now I have about ½ the legroom compared to the seat I held for 3 months, and I am forced to stow my laptop bag in the bin several rows behind my seat (you know what that means). I never heard from the crew or any CO rep again.
-I get to SJU and think, "At least my 15,000 miles will be re-deposited"… and I check the flight status on co.com. Lo and behold: only one passenger was upgraded, and he happens to have my initials. In my reservation, the IAH-SJU segment now reads “International Business.”
-I’m assuming the mileage will not be re-deposited into my Account (without action on my part)

I have no idea what happened here. I can think of several scenarios that might explain it, but I was in way too much of a hurry to figure it out. I was arriving in a Latin American city late at night and didn’t want to delay things any further. I should have complained loudly and immediately, but that's just not my personality.

Obviously, I am going to contact WE CARE about this. Someone clearly didn't do their job here. Any thoughts on compensation?