I will also try to update my project. if successful, I will tell you about the transition steps.
But the sencha blog says:
As a preview, the APIs are not frozen yet. This should be a fair warning. Since the API has not yet been frozen, they have not yet been guaranteed backward compatibility with Sencha Touch 1.x.
Everyone who visits SenchaCon later this month (I think this month is November) will also be able to visit Jamie Avins, talking about porting apps from Sencha Touch 1 to Sencha Touch 2
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