iPhone 3G to iPhone 4S

So my iPhone 4S is coming tomorrow, and Ive been using my iPhone 3G (that's right, still on iPhone 3G with iOS 4.sluggish) and I was wondering if I'll have any issues getting data from this phone onto my new one, such as texts, settings and apps to the new phone? Anyone have any insight to this?
Thanks

If you do a backup in itunes and then when you activate your phone restore it through itunes all should be well.

No worries. The transfer of data will be made from iTunes to your new 4S, not from the 3G to the 4S. As long as you've backed up in iTunes, the 3G could be completely dead and you'd still be able to migrate to the 4S.