Those who've heard the first two Eagles of Death Metal albums predominantly fall into two camps: either fully onboard with the tongue-in-cheek bluesy rock and offbeat shenanigans of frontman Jesse "Boots Electric" Hughes and Josh "Baby Duck" Homme, or left cold by their '70s-rock homage and accompanying antics, like those nicknames. (Which pretty much means you hate fun; but to each his own.) The band's latest, Heart On, may not completely sway the latter group (they do hate fun, after all), but it goes a long way toward proving the band isn't a novelty act or Homme's Queens of the Stone Age side project. Songs such as the ballad-y "Now I'm a Fool" sound little like previous material and reveal vulnerability(!) from the perpetually swaggering — if you've seen them live, you know that description is completely literal — Hughes, with lyrics such as "I was so sweet on you, and it feels like you faked it" showing some surprisingly non-awkward signs of maturity. Die-hards shouldn't fret; there are plenty of pure Eagles numbers here, such as the opening track, "Anything 'Cept the Truth," in which Hughes clarifies, "I say I love you, but you ought to know I only love the night." Phew. How sad can an album with a naked female posterior in the liner notes really be, anyway? Lead single "Wannabe in LA" may be the perfect synthesis of old Eagles and new Eagles. The track skips along for two gleeful minutes, but is paired with bummers such as "I came to L.A. to make rock 'n' roll, but along the way, I had to sell my soul." In the past, that wouldn't have been much more than a throwaway line, but given Hughes' self-confessed personal problems during the recording of 2006's dangerously danceable Death by Sexy, it might just be something that both the band's loyalists and detractors could likely agree was absent in past releases —sincerity.