While the show was up 1.4m on last year's premiere, Geri Halliwell's guest slot also scored a huge peak of 11.96m (51.9%) at 8pm.
Saturday's series seven opener averaged a hefty total of 11.3m between 7.30pm and 9pm, as 10.79m (46.5%) watched on ITV1 and 489k (2.1%) tuned in on HD.
Konnie Huq's Xtra Factor debut attracted an admirable 1.48m (6.9%) to ITV2 at 9pm, while a further 243k (1.3%) watched on timeshift.
X Factor buzz clearly boosted ITV1's other entertainment offerings: Odd One In and Magic Numbers entertained respective audiences of 4.08m (22.3%) and 3.02m (14.1%) at 6.50pm and 9pm - both posting significant week-on-week rises. Earlier, You've Been Framed amused 3.58m (22.8%) between 5.50pm and 6.50pm.
BBC One posted lower figures as a result: 101 Ways To Leave A Gameshow logged 2.82m (16.6%) at 6.10pm, then just 3.29m (15.8%) tuned in for Tonight's The Night, and Casualty took 3.84m (16%) at 8.10pm. John Bishop's Britain had a respectable 3.68m (16.9%) at 9pm, Live At The Apollo amused 3.64m (17.7%) at 9.30pm, and Match of the Day pulled in 4.01m (27.8%) at 10.30pm.
Elsewhere last night, Channel 4 mustered 1.07m (4.5%), 1.9m (8.9%) and 849k (4.7%) for The Queen, Big Brother and a special compilation of 8 Out Of 10 Cats. Over on Five, NCIS managed 875k (3.7%), after which a CSI double bill grabbed 1.57m (7.3%) and 1.22m (6.7%). Meanwhile, repeats of Dad's Army, Have I Got News For You and Vexed delivered 1.11m (4.6%), 1.86m (8.6%) and 672k (3.5%) to BBC Two.
Overall, ITV1 beat BBC One in primetime for the first time since June, with 27.9% [HD: 1.2%] to 18%. Channel 4 was third with 5.8% [+1: 0.6%], Five followed with 5.1%, and BBC Two averaged a poor 4.3%.
BARB ratings data supplied by Attentional