Archont

This lens is a very nice allrounder since the wideangle is impressive at 17mm but it can also reach up till 85mm zoom. With the 1.6X factor it is 27 - 136 mm.
I tested this lens with a friend of mine who bought the 350D kit with the standard lens. I turns out that the standart 18-55 lens can handle the comparison quite well up till 35mm. The differences are very small but dont forget that the standard lens only costs 50 euros instead of 480! In some cases the standardlens is even a tad sharper and the colours are slightly darker!

Somewhere in between 35 mm and 55 mm the standard lens loses its quality while the 17-85 seems to gain. At 55 mm the crisp and dark colours of the 18-55 lens get a setback compared to the 17-85. Also the pictures of the 17-85 turn out to be sharper at the full 55mm of the standard lens.

Onscreen at 1280x1024 you dont see a difference in any of the comparison pictures except you can tell the better quality of the 17-85 over the 18-55 at 55mm if you take a good look, especially at the colours. If you mainly shoot below 55mm and preferably mainly below or on 35mm you might as well go with the 18-55mm standard lens and save yourself the 400 euros. Even if you shoot up to 55mm just the qualityadvantage of the 17-85 is probably not worth the 400 euros. If you want to go pro you probably dont use any of these two lenses and if you shoot for serious fun you might not want to spend 400 euros to make up for a qualitydifference that is only shown at full focal lenght. You might as well go for the 18-55 in that case and add the extra money to save up for the 70-200L lens for example to get good coverage from 18mm all the way up to 200.

On the other hand, you dont buy a 17-55mm lens off course. You still have 30 more mm of coverage and it seems that the further you zoom the sharper it gets. Pictures with the full use of the 85 mm are even excellent while the lighting conditions are not optimal because you have the Image Stabalizer to rely on. Also the USM motor works like a charm. Even while searching for focus it runs up and down the complete 85mm very fast.

Summarized: the lens is worth the money if you like to use the zoom a lot while being able to make very decent pictures with the wider angles (which wont stand out in quality compared to the standard canon lens). I see it as a really big advantage to have very crisp pictures on 85mm zoom as well as decent wide-angle pictures in one lens with the IS ánd the USM. If you dont plan on using the zoom a lot and find it important to get the most out of the lens around or below the 35mm and to get best value for the buck then go for the standard 18-55. Limit yourself around 35mm and safe up for the zoom!