T-Mobile, where's my WM6 Update?

For some reason, it seems like every other carrier and device maker has put out free upgrades to devices running Windows Mobile 5. I want WM6 and can't get it. If I update my ROM on my current device with another carriers WM6 ROM, chances are good that something won't work right. In a worst-case scenerio, I brick my device. This is not a good enough option for me. Risk/reward are just not balanced correctly. I really wonder though why T-Mobile has missed the boat on this. It's such a simple service to your customer and by not allowing me to upgrade my device, you are technically proving inferiority to me in comparison to your competition. This is a random rant but I really was wondering how the rollout of such updates is determined. It isn't technically difficult and it's a minimal cost factor (as far as I can tell) when compared to the benefits. Maybe someone else knows more? Are there internal politics behind this?