The sharp spike in hits and files (green and dark blue) are mostly due to the new layout. The key statistic is daily average number of visits. Total visits are shown in yellow but that varies by number of days in the month so the daily average is the better metric.
The daily average number of visits was 5828 for January 2007 compared to the previous record of 5311 for December 2006 representing a gain of 10% month over month.
For those who haven’t been following UD very long the decline between August and October was was the result of being delisted from Google in the middle of September.