The best camera is the one that's available

http://www.gizmodo.com.au/2011/04/hey-some-people-actually-use-the-ipad-2-to-take-pictures/

In practice, the best camera is the one you have with you.  That's the only reason I ever use the camera in my phone.  Given a choice, I'd always use my DSLR.  But it's big & heavy, so it usually stays at home.

When something worth photographing appears, I grab the best camera available.  If that was an iPad, I'd use that. 

The photograph at the top of this item was taken using a Palm Treo with a resolution of 640 x 480.

If you find string theory hard to understand, this may help

Then again, it may not:

http://xkcd.com/171/

How much fuel does a hybrid realy use?

We've all seen the figures for fuel consumption, achieved on a test machine.  "Your mileage may vary," & in fact it does.

For some real-world, long-term (since 2007) figures have a look at:

http://www.google.org/recharge/index.html