I'm usually good at solving my own problems while flashing ROMs and and such, but this one has me stumped.
At first, I noticed that the Downloads section only had a couple of apps in it (after I flashed Cyanogenmod and Succulent Desire [this seemed fixed on SmokedGlass]) and I fixed that by uninstalling something in Settings.
Now, any app that I try to install FC's the Market app when it starts Installing.
I've deleted /data/app/com.android.vending and I've fixed permissions in ROM manager. Can anyone help?