The text, for those who are squinting:
You've been annexed by Aggie Nation
The Best Academics & Cleanest Program in the SEC WHOOP!
Real Football. Real Tradition.
This is the sort of thing designed to get you, Rabid Florida Gators Fan, riled up. ARE YOU RILED UP? Do you want to know if this is a sign put up by Texas A&M? (It's not.) Pretty sure Texas A&M doesn't have the best academics in the SEC? (Well, it's actually tied with Florida in the U.S. News and World Report rankings.) Want to know what makes Texas A&M the "cleanest program in the SEC"? (So do I?) Need to know if Gainesville has actually been annexed by Aggie Nation? (That is not how annexation works, though you might think so if you were educated in Texas.)
I'm not riled up. This is a move by some boosters with some money to blow who desperately want Texas A&M to be taken seriously by all its big brothers in the SEC. It's at 13th and 53rd, apparently, and that's so far from the main thoroughfares in Gainesville that 13th turns northwest (and into NW SR 20) at that point. I don't live anywhere near there, and I doubt many students do; I have lived in Gainesville for five years and gotten lost a lot and I'm not sure I have ever been by that intersection.
That makes me think the billboard was cheap, and the installation of it equivalent of a political campaign buying an ad in the smallest market in North Dakota and relying on the mainstream media to turn it into a thing. Do you want to play into the hands of a few A&M fans?
Edited To Add: As some of our esteemed commenters point out, this could also be the work of people (cough, Texas, cough) poking fun at A&M, in which case it would be a delicious troll and I would salute those fine people.