Gotta say, I'm not a big fan of Yui's latest single. I want to like all of Yui's songs, but this one is pretty "meh" and sounds like every other single she's put out in the last two years. It peaked at #1, but this is only its third week on the countdown and it's already fallen into the lower 20s.
Some singles with staying power include Jounetsu no Mariachi, which, as you may have guessed, has a mariachi band in it (and cracks me up every time I see Hikawa Kiyoshi cheesing in that ridiculous sombrero)and Maru Maru Mori Mori which has been on the countdown for 22 weeks. Maru Maru Mori Mori will never leave the countdown. In Maru Maru Mori Mori we trust.