On the basis of today's hitout, Callinan (rookie-listed, age 28) could certainly shape to be the next Podsiadly in 2011.
I agree Jason- on todays intra club hit-out Callinan is on the radar as well as Krakouer from the Pies and no bias here, Puopolo and Smith from the Hawks are ones to watch.
There are so many we could list - Swallow, Bennell, Smith, Day, Gaff, Conca, etc. - so perhaps just have a read through the forums and see what the general opinions are as to who will be the best ones. There are the ones who will likely be in basically everyone's teams such as Swallow and Gaff, which makes picking them give you no advantage. The advantage comes from choosing the right rookies from the 'others' So we could flood you with heaps of different rookies, without a any certainty that they will be the best. As i said, maybe have a read of other rookie posts, and see who everyone else is picking, and what the reasoning is.