I can't control the google auto update stuff, but I kept the old Market in the google apps zip just to let the issues get worked out first with the market. as far as now what you can do since it wont let you uninstall, use root explorer to find the market in your /data/app directory and delete the .apk from there, that will remove it if it is installed to /data/app which would be my guess.
There is no uninstall update for the market. At least I didn't see it. Can I flash back to my nandroid of DC11 that has the old market and purchase my app then flash back to 12? It should sync and show up?
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