This is a very good lens. The UD (ultra dense glass) element helps to correct colours and it is quite sharp. The aperture at f/2.8 is wonderful. It is pretty sharp wide open, and typically great around f/8-11 (though most lenses are) It has IS which is not all that necessary at this kind of range as...

The premium standard zoom for APS -C sensor cameras usually covers the range from around 17mm to around 50mm and has a maximum aperture of f/2.8. In 35mm terms this coverage is equivalent to something like that which a 27-80/2.8 zoom would have on a full frame camera.

This is the best glass aside from the 10-22mm you can get for your Rebel. I have been able to borrow a friends lens and the clarity of the photos you will get from this far outweigh the cost.

daily walk around lens; portraits

Yes, I would recommend this to a friend

Fast / accurate auto-focus

Weak Casing

The optical quality of this lens is excellent. It allows you zoom from 17-55mm at a constant f2.8. Other zoom lenses will change the aperture but it can hold this constant as you zoom so it does not change your timing. The wide aperture makes it great for shooting parties indoors.

Consistent Output; Fast / accurate auto-focus; Nice Bokeh

Heavy

I have always been a canon user but have never been satisfied with the system when it went digital. My ef lenses never worked quite right and the ef-s lenses left a lot to be desired. This ef-s lens makes a great difference. It is well made, fast and gives crystal clear images.

Easily Interchangeable; Fast / accurate auto-focus; Strong Construction

Heavy

Canon 7D + 32GB CF + 17-55mm f/2.8: Smifu rocks! An absolute pleasure dealing with Mark. Nothing was too much trouble, every question answered promptly, and all promises honoured. Delivery ahead of expected date, all products as described. Overall best price, and even after-sales follow up.

All in all this is the best sub-L lens (pro level) canon lens in the 'normal' zoom range and worth

Great images; reliable quality and ergonomic

EF-S mount; Small focus ring

Canon's EF-S 17-55mm f/2.8 IS USM is a premium zoom lens designed for EF-S bodies and announced alongside the EOS-30D digital SLR in February 2006. Boasting a constant f2.8 aperture throughout the range, it's the fastest standard focal length zoom lens available for Canon EF-S mount digital SLRs.

A quality modern mid range zoom for 1.6x crop with all the bells and whistles, constant F2.8, IS & USM. A bit soft at wide end at 2.8 which becomes sharper at f4. Like to see this lens upgraded to L quality for around the same price. Shoots good images but so does the 17-85 at f4.

Good images; IS; mid range zoom

Little Soft wide @2.8