50 Cent, "Before I Self Destruct" (Interscope) [1 STAR out of 4]

The expiration date for Curtis Jackson, a.k.a. 50 Cent, was obvious from the moment he made his mainstream debut with "Get Rich or Die Tryin'" in 2002: No matter how strong your ear for catchy hooks and thumping beats, there's only so much mileage you can get from the "baddest of the bad-ass gangstas" routine when we've heard it so many times before, especially when you have little to add besides endless prattle about how many times you've been shot and stabbed.

Fiddy tried to show a bit more range with "Curtis" in 2007, timed for a celebrated showdown on the pop charts with Kanye West's "Graduation." But you'll recall that West won, commercially and artistically. The melodramatically entitled "Before I Self Destruct" actually was recorded before "Curtis," but the "more personal" effort was swapped out for the darker disc at the last minute, and the 16 tracks here haven't grown any fresher while sitting on the shelf for last two years as 50 Cent's been busy selling vitamin water and courting Hollywood.

There are enticing moments, to be sure--it would be impossible not to have a few, with a top-dollar roster of production talent including DJ Premiere, Dr. Dre and Polow da Don. But the cameos by Eminem (on the tired and tossed-off "Psycho") and R&B superstar R. Kelly ("Could've Been You," one of two ill-advised Fiddy smooth jams) add nothing, and the millionaire businessman's rhymes about scheming bitches, treacherous drug dealers and his allegedly unrivaled ability to beat all rivals to a bloody pulp have never sounded more predictable, boring, contrived or thoroughly insincere.

Norah Jones, "The Fall" (Blue Note) [1.5 STARS out of 4]

Amid an infinite sea of rich, complex and at times challenging flavors, sometimes you just want a scoop of plain vanilla. There's nothing wrong with that, but even in the world of unfettered whiteness, there are degrees of quality, ranging from, say, a thick and creamy scoop of Ben & Jerry's to the generic, tasteless and ice-speckled stuff on deep discount at the supermarket.

Easy-listening coffee-house fixtures Norah Jones and John Mayer fall into the latter category. In both cases, this is nothing short of a crying shame, because each is capable of much better--30-year-old Jones with her sultry, smoky, sleepy-time jazz chanteuse vocals, and 32-year-old Mayer with his long-since-stifled grounding in credible electric blues. Yet on their fourth studio albums, both compromise their roots as never before, cheerfully yielding to the lowest-common-denominator demands of the pop machine to churn out buckets of blandness.

Jones is slightly more successful than Mayer with "The Fall," a title clearly meant to evoke the encroaching gray stillness of the season rather than her commercial potential. Though she turns to producer Jacquire King, a veteran craftsmen of hipster-rock efforts by Modest Mouse and Kings of Leon, a minimalist cabaret sound and somnambulistic mood prevail, with guest collaborators such as Ryan Adams and Will Sheff of Okkervil River doing little to elevate the lulling conformity of the songwriting. Jones does mellow chill-out reasonably well, but after a few tracks of it, you're thinking, "Snorah." Things only really pick up midway through the disc on "It's Gonna Be," a hypnotic swampy groove a la Dr. John, which underscores that this still-young artist could do great things if only she challenged herself a bit.

John Mayer, "Battle Studies" (Columbia) [1/2 STAR out of 4]

Meanwhile, though Mayer promises explosive excitement on "Battle Studies"--"Clouds of sulfur in the air/Bombs are falling everywhere/It's heartbreak warfare," he croons in the opening track--he veers closer to some unholy hybrid of Sting and Dave Matthews, and the romantic pap of the 10 original tracks fizzle like the embarrassing dud of a North Korean nuke. Laden with laughable romantic-schlock lyrics and trite, sappy melodies, these songs aim for the pathos of classic Carpenters but come closer to maudlin Barry Manilow. And no, neither the guest turn by Taylor Swift on "Half of My Heart" nor the two Boomer-courting covers--exceedingly lame, Lite-FM versions of the Cream via Robert Johnson standard "Crossroads" and Bruce Springsteen's "I'm On Fire"--do a thing to elevate the dross.