Hi missB,
I went to the OD in Hobart back in late July this year (I'm from Melbourne). About 45 people attended and only around 15 people got through for a final interview. Everything was done on the same day and interviews were arranged for the next 2 days. Pretty lengthy process as I was there from 8:30am through to 6:30pm. It's definitely easier in Hobart compared to attending OD's in popular cities like Melbourne, Sydney and Brisbane where there are hundreds of applicants. Makes it harder to stand out in such huge crowds.
Oh and a lot of the applicants flew in from other states. Mostly from Melb and Syd. Recruiters seemed unimpressed with the amount of people who flew in for the OD - they suggested more than once that people should wait for days in their own cities etc. BUT if you have family in Hobart, it's worth giving it a try. At least you can stay for a short visit, free accommodation and all
Anyway, I'll be joining Emirates at the end of November so if there's anything else you would like to know, I'm happy to share my experience. Good luck!