A handful of singers on The X Factor TV show - like Leona Lewis and Shayne Ward - have managed to buck the trend and enjoy more than a brief shelf life in the spotlight.

But for most of the performers due to entertain at two packed Ulster X Factor Tour Show gigs this week, this really will be their fifteen minutes of fame.

The final nine from the fourth series of ITV's Saturday night prime time will make appearances as part of a 27-date UK arena tour - kicking off in Belfast and ending at London's Wembley Arena on March 21.

Last year, more than 200,000 punters flocked to The X Factor tour shows, complete with money-spinning mobile phone concert competitions for the captive crowds.

For there is little doubt that The X Factor is more about entertainment and fattening creator Simon Cowell's cash cow than being an influential, taste-shaping showcase for new, creatively valid artists.

On its own merits, The X Factor's mixture of appallingly brilliant auditionees, soap opera feuding between the judges and the occasional, excellent singer is a formidable formula for mainstream, ratings grabbing entertainment.

And the crass, ever recurring contestant clichés - "It's such an incredible journey", "I want this more than anything else" and personal favourite "I'm not doing this for me. I'm doing it for them " - are wonderful slices of showbiz ham.

An astonishing 200,000 people auditioned for the last series of The X Factor in 2007.

And a whopping 12.1m tuned in for the final tussle between clothes shop assistant Leon Jackson and personal trainer Rhydian Roberts.

Also among The X Factor tour line-up is a dinner lady, primary school teacher, cruise ship entertainer and an asbestos remover - showing that the series CAN make dreams come true, even for a short time.

But, whether 19-year-old Leon can follow in the footsteps of Shayne Ward and Leona Lewis and establish a career beyond the fleeting, fickle few months of fame is anyone's guess.

Leon's debut single, a cover version of the 1999 Oscar-winning Mariah Carey/Whitney Houston duet, When You Believe, was a three-week Irish and UK Number One, shifting more than 400,000 copies.

But that is half the amount of Leona's X-Factor winning song A Moment Like This sold.

The word is that X Factor svengali Cowell is going to adopt the same long-term career strategy that he took with Lewis, for Jackson as well. Leonine-haired Lewis's second single Bleeding Love pleasantly surprised many with its cool, classy ballad groove.

And her debut album, Spirit has sold an incredible 1.6m copies - making her a bona fide star.

The 2007 runner-up, Rhydian Roberts may, like fellow pop-opera act G2, end up becoming a major CD selling act after signing a £1m deal with Cowell's label and with rumours abounding that the likes of Jim Steinman and Andrew Lloyd-Webber may be interested in working with him.

The series itself shows no sign of running out of steam either, with contractual guarantees that The X Factor will be made and screened until at least 2010.

As long as the UK's obsession with the pursuit of stardom and glorification of celebritydom continues unabated, The X Factor will remain one of this nation's favourite things.

Just ask the thousands of Ulster concert goers who have made the live show one of the hottest tickets of 2008.

? The X Factor Live Tour show, featuring Leon Jackson, Rhydian Roberts, Same Difference, Niki Evans and more, will be staged at the Odyssey Arena, Belfast tomorrow night and Tuesday night. Tickets, priced at £29, are available from the venue box office on 028 90739074, from Ticketmaster outlets and online at www.ticketmaster.ie.