Somebody must have liked Cher Lloyd’s “Swagger Jagger”.  It did get to number one, after all.  But it drops to number 3 on its second week, and judging from the midweeks, it’ll be out of the top 10 on Sunday.  Given that it had plenty of pre-release hype, the obvious conclusion is that it had little crossover appeal beyond her fanbase.  Which might be because it was terrible.

The new number one looks like another one-week wonder.  It’s the lowest-selling number one in almost two years, and it’s down to four on the midweeks.  But at least this one is an overachiever.

This is “Promises” by Nero, a dubstep group who previously reached 15 with “Me And You” and 8 with “Guilt”.  A lot of places describe them as a duo, but singer Alana Watson seems to be such a fixture on their records that if she’s not officially a member, she might as well be.

It’s the fourth single from their upcoming debut album – the other one, “Innocence/Electron“, came out last year and did absolutely nothing in chart terms, but that was before anyone was seriously promoting them to a radio audience.  Here’s the official video to “Innocence”, if that’s what you want to call a collection of 20-year-old clips from Cyber City Oedo 808.

Yes, Nero are number one because it’s a quiet week.   But it’s also one of the best number one singles of the year, and it’s a nice change to have a proper crossover hit at the top, in a year which hasn’t had very many of them.  I’m not sure the wall-of-sound epic production (with this year’s fashionable trick of slowing down and spreading out for the chorus) really comes across on the YouTube version, but perhaps that’s just my speakers.

Elsewhere: as expected, “Jar of Hearts” by Christina Perri continues its extended climb up the chart, having now moved 52-49-42-46-17-5.  That’s by far the most significant of this week’s nine climbers.

There are five other new entries.  Number 16 is “Titanium” by David Guetta featuring Sia, which doesn’t have a video.  This is a track from Guetta’s upcoming album, which has already produced “Little Bad Girl” (currently at 4) and “Where Them Girls At” (21).  But, in the odd hair-splitting world of the music industry, while those are promotional singles, this is a “promotional single”, and apparently there will be two more of them before the album proper comes out.  The difference, as far as I can make out, is that a “promotional single” doesn’t have a video, and they reserve the right to re-promote it down the road.

This track was originally recorded with Mary J Blige on vocals, and you can find that version on YouTube too.  For some reason, though, Guetta chose to remake it with Australian singer Sia Furler. She has in fact charted in the UK before, way back in 2000, when she reached number 10 with “Taken for Granted”, a song that sank without trace everywhere else in the world.

Number 28 is “Marry You” by Bruno Mars, which doesn’t have a video either.  This has been floating around outside the top 40 since the start of the year, but it’s now being promoted as a proper single.  Though not to the extent of actually making a video for it.  It’s going to climb.

And three others are scraping the bottom end of the chart.  Number 32 is “Rain Over Me” by Pitbull featuring Marc Anthony, another of his dance-pop tracks.  Marc Anthony is a Puerto Rican singer who’s been around forever, and like Sia, he’s got a couple of earlier UK hits you’ve probably never heard of – “Ride on the Rhythm”, which made number 36 in 1998, and “I Need to Know”, which got to 28 in 1999.

Number 37 is “Who’s Laughing Now” by Jessie J, which is now being promoted as the fourth single from her album.  Is it just me, or is it a bit presumptuous to be writing songs about how awesome your life as a pop star is on your debut album before you’ve actually found out whether you’re successful?  And number 38 is “Wet” by Nicole Scherzinger, which is self-explanatory.  Both of them make big climbs on the midweek chart, somewhat dispiritingly.