I don't know that much about jail breaking so here are a few basic questions.
Once it's done can you still use your iTunes music and apps?
If a new app comes on the AppStore can u get it or are you then restricted to non approved apps?
What are the major advantages for the iPad?
My main reason for JB would be running my iPhone as a wireless access point to give my iPad 3G access.

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Subaruless