In the battle of the normal zooms, it looks like the expected leader is already here, as the first few samples from the Canon EF-S 17-55 f/2.8 IS USM are already here. This lens is expected to set the standards for this range and lead against the Sigma 18-50mm F2.8 EX DC, the Sigma 17-70mm f/2.8-4.5 DC Macro, the upcoming Tamron SP AF17-50MM F/2.8 XR Di II LD Aspherical IF, and the still in the works Tokina 16-50 f2.8.
Note that as of writing, Google Pages is reporting a “bandwidth message” for the said site and images, probably a result of the sudden surge of photography enthusiasts eagerly awaiting the first real world samples from this lens.