Purchase: 60D or 7D + Lenses?

Hi All, i'm looking at purchasing either a Eos 60D or 7D, money is not to much of a issue but more so getting value for money out of the camera.  I'm only looking for a single lens something like the Tamron 18 - 270mm or Sigma 18 - 250mm.  So my questions and request feedback on are:

1. Picture quality from the 60d or 7d.  Much difference? or is it more so based on the type of lens?

2. With only a superzoom lens on the 7d does it negate any of its qualities and therefore the 60d is a better option?

3. As a 'keen' amateur compared to a 'professional' amateur photographer is the 7d and it's capabilities over kill on what i may ever use it for.

4. Why pick a 60d over a 7d and why pick a 7d over a 60d?

5. Any other lens which should be considered

Appreciate your feedback and thoughts and any other information you may throw would be good

Thanks