I do not know how it shows that the 12th season/series just started on TVRage, when every other website, and even the episodes themselves indicate that this is Season/Series 10.
It looks like Season/Series 8 was split in half on here, with the 2nd half showing as 9, and again with Season/Series 9 being split in half as 10 and 11.
In the episodes themselves, the interstitial graphics show "WD8" "WD9" and now "WD10" indicating Wheeler Dealers and the Season number. The episode numbering on other websites such as TheTVDB and Wikipedia reflect the correct numbering, but those on TVRage continue to be different.
TheTVDB Season 8: http://thetvdb.com/?tab=season&seriesid=81320&seasonid=242271&lid=7
TheTVDB Season 9: http://thetvdb.com/?tab=season&seriesid=81320&seasonid=343171&lid=7
TheTVDB Season 10: http://thetvdb.com/?tab=season&seriesid=81320&seasonid=462291&lid=7
I have just submitted numbering corrections a few minutes ago, and I hope to see that they are finally fixed!