One thing we all missed was the rear Quick Control Dial (the "nose wheel") found on all other Canon DSLRs. With the Rebel, you need to press and hold a button to make adjustments such as aperture in manual mode and exposure compensation in program mode. It slows things down. You can, via custom functions, program the four-way jog buttons to control such settings as AF point selection, but this double duty invites mixups. Canon, give the next Rebel a nose wheel!
Among other control annoyances, flash exposure compensation is relegated to a menu rather than an external control. Yes, you can program the jog buttons to control flash comp, but we think it should be a more obvious (read, clearly marked) control. And a few too many controls, such as ambient exposure compensation, are press-and-hold affairs.
The new Reb uses the autofocusing system of the 30D, with its 9-point wide diamond pattern. Somebody at Canon has been stirring the mix, though, as the Rebel AF tested out both faster and more sensitive than the 30D. Moreover, the AF proved as fast if not faster than the AF on the Nikon D80 and D200 -- even down to a very dim EV -2 (at ISO 100), previously the sole province of the Nikon rigs.