It's becoming harder to convince my friends that buying only Canon gear is the right thing to do.
Sigma have put out some amazing lenses in the last two years and Canon's only memorable release is the Canon EF 24-70mm F/2.8 L II.
I guess "memorable" is subjective, but over the past couple of years Canon has released, in addition to the lens you mentioned, the 24-70 f4, 24IS, 28IS, 35IS, 40mm pancake, and 200-400L, all of which are first rate regardless of whether one may actually want any of them.
Agreed, Canon has made several memorable lens releases. The 24-70 and 200-400 are probably the most memorable, but most people who have one seem to rave about the forty shorty, too!