Ernest changed it to conform to the original color code in the legend below the map.
The link provided shows a growing acceptance of same-sex marriage, and that continues. In 2004, they were 38% in support. Now it's 47% in support. Most those polls report an error of a few percent, which could explain the slight difference in the last two polls (48% earlier this year, now 47%), but overall it's about what you'd expect given the trend in Ohio.
As for the color change, there was a slight support earlier this year, now there's slight opposition. Actually, reading that as noise, you could call it a tie, but I think Ernest reserves yellow for reported ties, not statistical ones. It's probably best that he sticks to the original color scheme, otherwise it becomes conjectural. Don't read too much into the small fluctuations. These polls really aren't all that scientific, and a five percent difference is not unusual.
