[doublestuff]

Southeast Florida definitely has an iguana problem, although it varies locally. I left Florida in 2003, and returned in 2010. When I left I had never seen an iguana in the wild. My first drive to the Keys after coming back I couldn't keep count of them (over 100). I've seen them all over Monroe, Dade, Broward and Palm Beach counties.
I live on the west coast (Naples), and I've seen a couple here, but not anywhere near the numbers I see when I visit the east coast. We do have Cuban anoles (about 20" long green lizards, mostly seen in trees), but I think I've seen three or four of them.
When I moved back to Florida and lived in Palm Beach County for a bit, I walked out to my car one day and was surprised to see a two-foot-long Basilisk lizard (aka "Jesus lizard" for its ability to run on water) next to my car. Apparently a shipping container of fruit came from Honduras to the Port of Palm Beach - when they opened it, a bunch of Basilisks ran out, and now they have a breeding population.
But yes, to answer the OP's query, iguanas are an invasive species that are present in Florida in increasing numbers, they cause quite a bit of damage, and we should probably start eating them. I do think they're adorable, though.