I fully support exploring ways to bring in more votes, but i think opening the eligibility to "everything and anything" is more than a little self-defeating and takes away from the very meaning of the awards.
I think you're on the right track but took the wrong train. Here's how i think you could expand eligibility without opening the floodgates to making this year's awards about the Entire History of the Forum.
Things that transcend calendar years - i.e. fan fiction. A lot of fan fiction is written and posted chapter by chapter instead of all at once leading to situations where something might have been started in one calendar year but finished in another. If any part of it was written in 2010, i would consider it as being eligible.
Same thing with long running threads. For the best thread category, if it had participation in 2010 but was started earlier, i'd consider it valid.
Situations like those are things that could easily be expanded without any problems. But something that didn't have ***anything at all*** to do with Jan 1-Dec 31, 2010, not so much (and quite honestly, if someone was in the running for a 2010 award and lost it to something that wasn't 2010-related, they'd have every reason to feel quite slighted and ripped off)
Now the one exception to that would be the Lifetime Acheivement Award since Lifetime Acheivement Awards by nature are historic - someone could win a L.A. Grammy for example even if they didn't have any new material in the past year. (But even then, i'd kind of have a hard time voting for someone who didn't post at all in 2010, but that's just me.)
If the deadline for voting needs to be expanded and the date of the awards changed to get the needed amount of votes in, that's not such a bad thing - certainly a far better option than something that mucks up the value/meaning of the existing awards.
Another possible solution is to have two rounds of voting. (I think i might have mentioned this possibility last year) First round determines nominations. Nominations can then be announced for final voting for the award winner itself. This method (a) expands the time to get votes in (b) brings in more voters - those that have a harder time choosing have a smaller list to choose from and can also go back and research those specific nominees (instead of trying to remember the entire last year) (c) a nomination list refreshes people's memories of some good stuff they may have forgotten about or not considered (d) In some categories that have such a large amount of possibilities like Best thread or Best Post, it helps eliminate the real scenario of having a 30-way tie because each voter chose something different (e) expands goodwill because more people who didn't ultimately win an award can at least see they were nominated and feel good about that.
...At any rate, even if the new rules still stand where we're now voting for *anything* from the forum's history as opposed to the last year, i personally would still vote for 2010 stuff only and hope others would do the same. As mentioned, i fully understand and sympathize with needing more votes and looking at ways to solve that issue, but if in doing so, you dilute or mess up the very meaning of the awards themselves, then the solution ends up far worse than the initial problem.
(I know i probably think about this kind of stuff way too much but having worked ten years for a market research firm does that to a person...even if it's been another ten years since i was fired for being gay)