UPDATE: If anyone is going to be there and wants to have a beer, let me know (or leave a comment if you'd like). Also, if you go and have photos please post to the Hail the Ale! Flickr group. If you don't use Flickr, just email me and I can arrange to upload them for you.
They have a nice list of beers this year, including my local favorite Orlando Brewing. Here's the brewers I'd suggest checking out:
Yuengling: They'll be serving the Lager, Black & Tan, Light Lager, Porter, and Ale. These are all solid beers and the Yuengling staff (yes, they actually have their own staff there) are always nice and don't mind answering your questions.
Orlando Brewing: They'll have their Blond Ale, Pale Ale, and Blackwater Porter. Over the past few weeks, I've tried all of these and would recommend you do the same.
Margaritaville: They have Lone Palm Ale which is a good beer but last year they were also serving their Margaritaville frozen foods (cooked, of course).
Sierra Nevada: Need I say more? OK, I will: they make some damn fine beers.
McGuire's Irish Pub: This was probably the best kept secret of last year's festival. They were kinda tucked away at the top of the stairs by Bob Marley's (I think…) and had some really great beers. This year they'll have Bagpiper's Special, What the Gentleman on the Floor is Having, and McGuire's Raspberry Wheat.
Of course, there are other good beers to be had, but these are some you may not have had or can find everywhere.