I think that the captaincy will remain with Neita for the 2008 season, with Brock McLean, Junior and Green taking the mantle for games in which the Big Fella is injured or (perhaps) rested. Their performances as captains during these games - as well as their off-field leadership - will probably determine which of the three will become captain in 2009.
While I think that we should pick a long-term captain to replace Neitz after he retires, I don't necessarily agree with "just giving" it to Chook. If you look at the performances of St. Kilda's recent young, one-year captains, none - with the exception of Lenny Hayes - have been able to play consistently or injury-free during their respective years as skipper. This is particularly true with Nick Reiwoldt and Luke Ball (whom, incidentally, I view to be very similar in talent, mindset and injury-proneness, to McLean.)
The most important thing for Melbourne now - as we have such a young list - is to get the most out of our aging players, not only performance-wise, but also in terms of their ability to lead and teach new players. Having said that, however, in order to maximise Neita's longevity as a player and leader, I believe he should be rested a couple of games this year, which may enable him to give one more, unburdened, captaincy-free season in 2009 - one in which he is able to maximise his goal-scoring ability while minimising his risk of injury.
In 2009, Melbourne, with its group of young stars; Bate, Jonesy, Newton, (hopefully) Sylvia, Rivers and Moloney - with McLean as captain and on-ball giant, accompanied by good seasons from aging players such as Green (played only in the forward line), Bruce (forward, bench and midfield), Junior, Robbo and Neita in his last year, may have its first real crack at a flag since 2000's inevitable loss to Essendon.