Your lucky your weather is nice there.  Mostly here it is too rainy to take
outdoor pictures these days.

I love my 28-135IS.  It's a fantastic lens (at least for me!).

It's a great picture, but the point of panos is to go _BIG_, like at least
10000 pixels wide, not reduced to look like a crop from a wide-angle.  The
fun is zooming way in and back out, enjoying the amazing coverage, detail
and depth of field, panning across at 1:1 imagining the huge print that
would show it all even though I can only see 1600x1200 pixels at a time at
101 pixels per inch.

I'd love to see this one done big, like really big.

That's a very interesting test, considering the $600. difference.  I
notice the 24-105 is the "L" series.  Does the 28-135 IS have the same?
 I think this is Canon's patented "L" glass coating.  A very
interesting comparison, Bret.  Thank you very much for taking the time
to test them out.  Looking forward to more comparisons.
BTW, we're having a mild December as well......SO FAR!  Weather-man
says it's the El nino effect.  
Helen

From what I've seen on the web, the biggest differences are at the wide
end. Below is an intersting review and comparison.
http://www.luminous-landscape.com/reviews/lenses/24vs28.shtml

I think I would prefer the 24-70 f2.8L myself, from what I've read it
compares well against primes and is optically better than the 24-105 f4L
IS.
http://www.luminous-landscape.com/reviews/lenses/28-105.shtml

Cody,

http://community-2.webtv.net/AnOvercomer02/PhotographyLinks