Same here (Mexico-Telcel)
I was quite surprised when i saw that update. I have a 16gb 1gen with monthly plan on the official carrier for Mexico: Telcel. In Feb, i bought my iphone, unlocked with ziphone (yeah, i know, sorry), recently i upgrade to 2.0 with winpwn and that update pop up.
I was feeling "fearless" and i update. Actually it works very good, my carrier logo was MX TELCEL but only shows MX T...., now shows TELCEL, my edge works, even some extra services.
Making some research i found this link, regarding my update: http://appldnld.apple.com.edgesuite....Telcel_mx.ipcc
And looking within the file, i could find all of the settings that a regular iphone or any other phone by this carrier (telcel-mx) has. Now my iphone is complete, i got edge, youtube, clients support (yeah, wait for my call), and some silly shortcuts.
But definitly is because i got a monthly plan with this carrier, don't think this will work with others. don't know if anybody can customize this files with their "non-official" carrier specs, but it may worth the try.