I agree, in that I like the new polling system over the old way, but do see the issues with ties possibly becoming a problem. I thought the same even before reading you response above, that there would always be a chance of a second tie, if there were a re-vote needed for an initial tie.
Just some thoughts...
First, is there a way to set up a three vote polling system? (Edit: just happened to see Charlotte's post above after posting)
Second, I kind-of think the who got the votes first would work, but still doesn't seem fair in a way? Lets face it, some don't have the luxury to get on here anytime they want. Some might just have issues signing in, or issues with their internet, computers, etc., and were not able to get their vote recorded in a timely matter. ... I can also see apologetic post following, saying stuff like 'I'm sorry I wasn't able to vote earlier, etc.'
Lastly, maybe just do one of the following.... Simply ask everyone who chooses to vote, to do both? I mean, simply click the poll for their first, clear choice, and also do a quick post stating who their three choices overall were. - I know this might seem redundant to some, but it would be helpful to the admins in the majority of the challenges. This would help the admins when there was any clear winners, but having the additional votes as well, would then only come into play when there was a tie. - Or, simply have two winners? I know the winners back on the IFX forum would get their images placed in the mag, but with this site, couldn't we simply show there was a tie for that month?