Had someone told me, back at the start of this decade, that in eight years time one of the BBC's biggest ratings winners would be a pro-celebrity dancing competition I would have held them down and called for an ambulance. Had they gone on to tell me that I would become a confirmed fan of the show, I'd have hailed a taxi and taken them to the hospital myself. How wrong I would have been.

Strictly Come Dancing - or "Strictly" to its growing army of fans, is the pro-celebrity dancing competition of which I speak. A growing field of celebrities (this year there were 16 at the start) are paired off with a phalanx professional ballroom dancers with a stack of world titles between them. The show has made household names of the likes of Brendan Cole, Anton du Beke and Lilia Kopylova.

The celebrities, in contrast with a majority of such shows, tend to be genuinely well-known. Past winners include Natasha Kaplinsky, Mark Ramprakash and last year's runaway winner Alesha Dixon. Many of these celebrities have never had any form of dance training before, and the enjoyment for the viewer comes from seeing which ones take to the floor like a duck to water, and which go down like a lead balloon. Often this has surprising results - last year's intake included former competitive gymnast Gabby Logan, who should have been an extremely good bet to win but eventually exited the competition before her flat-footed husband, rugby player Kenny Logan.

This year's original group contained the usual mix - ex-professional sportsmen (Austin Healey), soap stars (Gillian Taylforth, Jessie Wallace, Phil Daniels), pop singers (Heather Small, Rachel Stevens) among others. From the early shows you can generally tell into which one of three categories the celebrity falls - natural, potential and awful. An easy way to spot an awful dancer is to check who has been paired with Anton du Beke. A phenomenally skilful professional dancer, du Beke has been paired in recent years with the atrocious Kate Garraway and, this year, the early departee Gillian Taylforth.

Along with phone-in votes from viewers, the dancers are eliminated one by one at the behest of a quartet of judges - the acid-tongued Craig Revell Horwood, the pun-addicted Arlene Phillips, head judge and kindly uncle Len Goodman, and the eccentric Bruno Tonioli. Along with watching the dancers, rating and giving them feedback the judges also parry weak banter from host Bruce Forsyth. Forsyth is assisted in his calling by Tess Daly, whose main role is to sneer at the judges' supposedly cruel remarks. These remarks generally come from Revell Horwood who, dare I say it, tends to be right more often than any other judge.

The dances with which our celebs are faced range from technical ballroom routines like the Viennese Waltz to showy, glitzy Latin dances such as the Samba or the Cha-Cha-Cha. A recurring theme in the show has tended to be where a celebrity deals well enough with the ballroom routines, but cannot master the quicker Latin steps. In some sense, this sees the show tending to favour the younger, fitter celebrities - although these celebs themselves need to make sure they get the hang of the ballroom moves as well.

The show's brassy, bouncy theme tune is fast becoming as recognisable as more established TV themes, and really builds the excitement for the viewer, who invariably will have chosen their favourite by Week Three at the latest. Choosing a favourite really gives the show an edge, especially if they turn out to be a contender (like my choice for Strictly '08, Austin Healey), but even if you don't, there are laughs to be had at the awful dancers, and marvels at those who turn out to be really good. Among those that live long in the memory are Alesha Dixon's Cha-Cha-Cha with professional Matthew Cutler, which came within a single mark of getting a top score of 40, as well as Matt di Angelo and Flavia Cacace's Waltz, which went one better (judges mark each dance out of 10, scores are then added together - in conjunction with TV audience votes these go towards deciding which dancer is eliminated each week.)

One drawback about the show is the weighting given to the public vote, which each year sees a poor but popular dancer stay in the competition at the expense of a better performer. Even with the introduction of the dance-off round (where the two lowest-scoring couples on combined scores dance again and are then at the mercy of the judges as to which has done better) to give the judges a greater measure of control over who stays in, we often find ourselves watching two half-decent couples dancing for one place while a less-gifted dancer cools their heels backstage. This year, the fornat has worked in favour of the charming-but-terrible John Sergeant, while last year Kate Garraway saw off much better dancers due to a series of sympathy votes.

The scoring system, though, is a minor quibble as the show brings a touch of glamour and excitement to long winter evenings. Saturdays at this time of year just wouldn't be the same without it.