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Hello all does this tomato plant have blight? It is the only one of my tomatoes that has this.

Yes, it does look like a blight or wilt of some kind. Looks like you are growing in pots. Are the green tomatoes the first or are you toward the end? Remove the yellowing leaves and see how it does. Yellowing sometimes means a nutrient deficiency but if it is treated the same as your others, that makes it a mystery. Don't handle the other plants after handling this one unless you have disinfected hands and tools to keep the disease from spreading. Most tomatoes degrade toward the end of their life and are susceptible to disease more that earlier in the season.

I'm getting similar yellowing on some of mine -- could be too much water since they are where water puddles when too much rain, but the yellowed leaves are already or susceptible to early blight infection so I do remove them as they appear. More septoria showing up, too -- typical of this time of year.

What variety is this plant? If determinate, then could also be early senility especially if stressed -- water (dry/wet cycle) or fertilizer, but again will be first to catch other fungal diseases.

That is the strange thing about it, There is a cherry tomato planted in the same pot and it is showing no signs of any disease at all, nor is the other pot next to it or any of the tomatoes I have planted in the ground.

Yellow is a very good indicator of very low nitrogen in tomatoes. If you do not fertilize and soil is depleted there will be a nitrogen shortage. Tomatoes do not need much nitrogen but they do need some. Worse thing you can do to tomato plants is give them too much nitrogen you get all plants and few tomatoes. If you mulch with wood chips, tree bark, tree leaves, saw dust, that will pull nitrogen from the soil and you get yellow leaves. Once it gets bad enough leaves die. There is a name for this condition but I do not remember what it is called. If it gets bad enough it can not be corrected. Your whole tomato plant is a very pale green yellow color.

Give your tomato plants some nitrogen soon as you can this condition should clear up in a few days if they are not beyond recovery already. Plant 3 beans about 3" from the tomato plant in 3 different places around the plant. Beans put nitrogen in the soil but this will take almost a month to take effect it is best to do this the day you plant tomatoes.