Oh sorry I missed this. Yes this is a good idea.
I tried to do this with the news items this year. Previously it had just been open ended text which took a lot of extra work to process, so I tried to narrow it down to the most popular/discussed/evocative topics of the year.
I had planned as the year went on to keep a better track of news, so might do the same with customs and either post a list to shortlist at the start of December or include as many as possible. Putting together the post of all the board banners for the year took a while so that's all I had time for this year.
For international works (art, fanfic, customs) I'd only include those shared here - lest the list get long.
If someone wants to keep track of the third party items released in 2012 and can provide me with that, I can expand on those too, but haven't previously because I don't keep a good track of them (since I don't buy them) and I'm conscious about the 'promoting third-party items' stance (but on the same hand think there's enough interest in them to include them in the awards).