I might be because it uses Flash to run and your version of Flash needs updated. Only use the Adobe site to check and update it.
I checked the site out on another computer running Avast and it came up that it blocked VBS Malware-gen which is a virus/worm.
I have notified the moderators to have it investigated.
On looking on the Avast forum there are a lot of reports about this. It is suggested due to the number of reports about it that the report is a "false positive" and Avast are working on a fix.
EDIT: If you download the latest update Avast appear to have fixed the issue.
Many thanks for all your responses.
I deleted all cookies etc. and restarted my computer and it seems as though this solved the problem, fingers crossed.