Although I've not seen his work in person, there is a guy posting under the name FinerDetails in the 'gallery' section of the above forum - the work he does on cars is simply astonishing.
Over the past year I have had 4 cars detailed and will get the Ferrari done again in Spring. The difference after the machine polishing/paint correction is awesome. As long as your car washing techniques are good then the effect is long lasting.
As for the leather, I did post something a few months back when I had the F355 seats treated. Again, the final effect is unbelieveable and fantastic value for money.