X Factor 2012: Tulisa Contostavlos and Nicole Scherzinger show off their impressive derrieres in tight and bright ...

By Sarah Fitzmaurice

PUBLISHED: 05:43 EST, 16 August 2012 | UPDATED: 06:02 EST, 16 August 2012

Cleavage has had its day - when it comes to oozing sex appeal it is all about showcasing a curvy derriere.

Tulisa Contostavlos and Nicole Scherzinger showed off their impressive and pert behinds stepping out in figure-caressing dresses at the launch of the new series of the X Factor in London today.

Last year's winning judge Tulisa dressed in a skin-tight Herve Leger bodycon dress in citrus hues for the occasion, and the frock certainly complimented her curves.

Tight and bright: Both Tulisa Contostavlos and Nicole Scherzinger opted for figure-hugging dresses for the launch of this year's X Factor today

Derriere delight: Tulisa Contostavlos and Nicole Scherzinger showed off their curves in tight dresses at the X Factor launch today

Tight and bright: Both Tulisa Contostavlos and Nicole Scherzinger opted for figure-hugging dresses for the launch of this year's X Factor today

New recruit for the UK show and Former Pussycat Doll Nicole took note of the sunny weather and donned a bright white shift dress to attend the press day at the Corinthia Hotel.

The demure outfit had capped sleeves, rouched detail under the plunging neckline and an exposed zip trailing up the back.

Nicole, who was axed from the US show after just one season, replaces Kelly Rowland as the fourth X Factor judge.

Tight and bright: Both Tulisa Contostavlos and Nicole Scherzinger opted for figure-hugging dresses for the launch of this year's X Factor today

New recruit for the UK show and Former Pussycat Doll Nicole took note of the sunny weather and donned a

She's a bit of an all-white: Nicole Scherzinger donned a bright white shift dress enhanced her figure and her derriere

The girls were joined by veteran judge Louis Walsh, host Demot O'Leary and Xtra Factor presenter Caroline Flack.

Gary Barlow, who recently suffered a personal tragedy - daughter Poppy was stillborn - did not attend the event and is with his family in mourning.

And Caroline's sidekick Olly Murs was also absent today because he is currently touring.

Here come the girls: Tulisa and Nicole shone as they posed up to Louis Walsh and Dermot O'Leary

Here come the girls: Tulisa and Nicole shone as they posed up to Louis Walsh and Dermot O'Leary