I was under the impression that it used to be driver's license, voter registration, lease, and you're good to go after 1L, but the updated legislation changed that. Comparing the 09 version (http://www.flsenate.gov/STATUTES/index.cfm?App_mode=Display_Statute&Search_String=&URL=Ch1009/SEC21.HTM&Title=->2009->Ch1009->Section%2021#1009.21) of the legislation you mentioned to the 08 version (http://www.flsenate.gov/STATUTES/index.cfm?App_mode=Display_Statute&Search_String=&URL=Ch1009/SEC21.HTM&Title=->2008->Ch1009->Section%2021#1009.21), you'll see that the 09 version requires one to have been living in the state 12 mo before INITIAL enrollment at an institution, whereas the 08 version didn't include that. Seems that they have pretty much eliminated the possibility of reclassification if you start as an out of stater, which is disappointing.
Anyway, thanks. Are people finding any summer internships there?
You're reading the statute wrong/not enough. It's saying that to initially classify as a resident for tuition purposes, you have to have been in the state for 12 months prior to enrollment and if you haven't, then you're a nonresident. However, after you've lived in the state for the requisite 12 months, you can reclassify as a resident if you've done everything else you need to. See (6)(a):
Except as otherwise provided in this section, a person who is classified as a nonresident for tuition purposes may become eligible for reclassification as a resident for tuition purposes if that person or, if that person is a dependent child, his or her parent presents clear and convincing documentation that supports permanent legal residency in this state for at least 12 consecutive months rather than temporary residency for the purpose of pursuing an education, such as documentation of full-time permanent employment for the prior 12 months or the purchase of a home in this state and residence therein for the prior 12 months while not enrolled in an institution of higher education.
As for summer work, yeah, people are finding work. Most people have something lined up, and I think most of the rest will get squared away soon.