I am running the official OTA 2.2. When I wake and unlock my X, sometimes the CPU jumps to 100% and sticks there. Naturally this makes the phone very laggy and burns up the battery. I checked in SeePU and it said the Kernel was causing the spike. This doesn't go away until I reboot the phone.
I'm using LauncherPro, and have quite a few large widgets running (including 2 scrollables). But I never had this issue on 2.1.
To someone without SeePU installed, this would seem like a VERY laggy phone after waking & unlocking.
Also the battery usage screen force closing seems to accompany this.