Without being able to see the identities of the voters, one should apply a healthy level of skepticism to the poll results.
There's some circumstantial evidence that the people behind SX OS are creating at least some accounts on GBATemp in order to hype their product and inundate the forums with posts about how it's significantly superior to any free alternative.
In addition, the OP created his account just to post this poll, and the first post reads like an advertisement. I wouldn't be surprised if the thread was an organized effort to present the SX OS as the most popular option. When I noticed that a plurality of voters voted for SX OS but that a majority of people voted for something other than SX OS, I intentionally pointed out this fact in an effort to see if there would be a sudden jump to a narrow majority for SX OS, and there was.