After listening a few times on the iPod and on the radio, it is what I expected. It's a great song, but not one of their iconic songs. However, it sounded great on the radio and if radio plays it out, it may become one of their memorable ones.
I didn't expect lead single quality for a free download. It's a step below, but I'm not complaining. If, they think they have better songs on the album than this, we should be in good shape as U2 fans this year.
By the way, video preview on Facebook looks amazing!