I was there for a couple of hours yesterday, and enjoyed it for all that. Paulaner is IMHO a reasonably drinkable beer, speshly compared to what's usually available in pubs around. The ability to have a nice sausage inna bun does add to the atmosphere, and the beer tent/hall if you could get a seat, would be great craic!
Edit: There are something like 14 stalls there, about half selling food and half selling Paulaner as well as the big beer tent that has music on. About half are on the floating island in the Dock, with the others spread around above that - be careful, though, if you buy a beer on the outside section you can bring it onto the dock, but the security guys won't let you bring beer back out, probably to try and reduce glass "liberation."
Oh, yes, there's a deposit on the glasses. Even the nice plastic ones.
I'd probably have been disappointed if I left from Cork to see it for the day, but then I didn't, and an hour on the bus up and back wasn't too much. I enjoyed it!
Paulaner Oktoberfest brew is 6%, and quite filling, in a "gassy" way. Nice though.
Oh, and the people seemed to be somewhat German - there was an air of authenticity!