THE ongoing digital revolution has pressured the global music industry into some interesting directions. Middle-of-the-road pop naturally remains a mainstay, but the year has had a distinctive retro flavour.

A whole bunch of vintage acts swung by our island to perform. Black Sabbath, Megadeth, The Cure and Arrested Development came for the very first time. Eric Clapton and America returned. You could almost hear a wave of middle-aged cheers at this influx of nostalgia. If you closed your eyes and just listened, you could pretend you were stuck a couple of decades in the past.

The retro trend looks like it will last at least until the beginning of 2008. Sting, not content with his successful solo career, has regrouped The Police and will be coming here in February, as will guitarist Carlos Santana. Such is the perceived demand for these two acts that the top ticket price for The Police is $600, while Santana is commanding up to $350.

The Police look like they'll be the best-selling - and highest grossing - tour of this year, taking in over US$171 million in 53 shows, so at least we'll have company in shelling out for exorbitantly expensive tickets. Since they've already milked their return thunder a fair bit this year though, it will be quite surprising if they manage to keep up the momentum in 2008.

The Eagles performing at the Singapore Indoor Stadium.

The Eagles were arguably the ones that started this lucrative reunion business in 1994 when they froze hell over and starting touring. They've been at it too this year with new album The Long Run and plenty of tour performances, though there's no news on whether we'll see them here any time soon. If they do come, Don Henley's declaration to CNN that the new album "is probably the last Eagles album" that the group will ever record would likely make their tickets as costly as the last time they were here in 2004. Their top tickets went for $499 back then.

The biggest question mark now hangs over Led Zeppelin - that monster of a classic rock band. They reunited for a sold-out London charity concert on Dec 10, and guitarist Jimmy Page told Canadian newspaper The Winnipeg Sun that he'd be "really surprised if there wasn't" new material to come from the reunited outfit, which features late drummer John Bonham's son Jason filling his dad's musical shoes.

All this talk about who's back together again would be incomplete without mentioning one of the biggest teases of the past few years - Guns N' Roses, or what passes for it these days. Axl Rose is the only remaining original member, and the supposed new album Chinese Democracy has been rumoured since 1994.

The band's road manager Del James said in February that the album has been recorded and is now in the mixing stage, but goodness knows when we'll get to hear it. Chinese Democracy may have been a no-show in 2007, but if by some miracle it surfaces in 2008, it would be pretty big. Stranger things have happened.

At least most of the members of these retro acts are still alive. 2007 began with a significant death, and ends with another one. The jazz world lost Grammy-winning saxophonist Michael Brecker, 58, to leukaemia in January. On Sunday, jazz suffered again when long-lived pianist Oscar Peterson died at 82. Brecker's final album, Pilgrimage, was released posthumously in May and has been nominated for two Grammy Awards. If the album wins, it will be a fitting tribute to a saxophonist whose influence was compared to that of the legendary John Coltrane.

The Asian music market has also seen some interesting developments. Retro figured less prominently although Japanese rock band X-Japan did reunite in June and begin touring, which should please legions of fans who never thought that they'd see the day, especially after guitarist Hide's suicide in 1998. Jay Chou is bigger than ever and is still the undisputed king of the Chinese pop world. November saw him release his eighth album, On The Run. If his previous releases are any indication, it should sell millions of copies even though Chou sings only in Mandarin. His January concert here sold out instantly and although top tickets initially sold for $350, they are commanding much more than that on the black market and auction websites.

Looking ahead, it is unlikely that the coming year as a whole will be as dominated by retro acts, since there are only so many big-name bands out there that can re-unite, and almost all the bigger names already have. Admittedly, however, crystal-ball gazing is hazardous in this industry where pigs occasionally fly.