RIHANNA
The pop queen perched demurely on a branch of a fiberglass tree as the show opened, singing the first verse of ''Love the Way You Lie (Part Two).'' It's a somber ballad, maybe an odd choice to kick off the night's festivities — but soon enough, Rihanna hopped down and launched seamlessly into her wildly catchy hit ''What's My Name,'' followed by a spirited rendition of the similarly up-tempo ''Only Girl (In the World).'' Nicely saved. Grade: B+