Chris Walsh (@ChrisWalshie) describes the WP7 update as "massive," and says that "MS took 3 months to do what Apple did in 3 years." He goes on to say that Microsoft "could have called it Windows Phone 8." This is music to our ears.
While Windows Phone 7 is a terrific OS, and is showing early signs of success, it's still lacking some necessary features. These deficits might be holding back the success of WP7 devices in general, particularly because most consumers aren't aware of the update. The update should fill some of those gaps, bringing copy/paste, multitasking, custom ringtone support, and Bing improvements like turn-by-turn directions.