We are predicting that online Mega Monday this year will be 14th December 2009.
In previous years it has been predicted to be the Monday of the first full week in December, but although the 8th was big last year the 15th surpassed it.  This phenomena is caused by

Monday is always peak trading day of the [...]

Article from Retail Bulletin
The re-launch of the TJ Hughes online store at the beginning of June was the key to its impressive recent sales figures that showed overall like-for-likes sales growth and its internet shop growing by 80 per cent for the first six months of its current financial year.
Steve Goodheart of the Transaction Partnership, [...]