Damn, for some reason my H2X games didn't transfer when I changed my gamertag. I just checked B.net.
I remember I had ~2,000 games played when I switched out H2 for H3. My last game was FFA Slayer on Beaver Creek.

I don't have access to the email I used to sign up for XBL anymore, I just barely changed it to my current email, so if I get my XBL points, I will be pleasantly surprised.