On Joba ...
I respectfully disagree with Mr. Zipper's post below for the following reasons:
1. Rivera and Chamberlain aren't similar pitchers. Mariano's never exceeded two plus pitches while Joba, by all accounts, has four major league offerings. I get that Rivera is the easy comparison given that he came up in the Bronx as a starter and thrived as a closer but they are very, very different. Frame, repertoire, development path (Mariano was already 26 when he began contributing), everything.
2. In a general sense, 180+ innings is always better than 80 innings regardless of leverage. You don't take a consensus top 5 prospect and cut his participation in half unless he proves he can't handle a starter's work. Chamberlain thus far has done nothing to indicate he can't.
3. In a more specific sense, Joba needs to throw around 150 innings this season after getting a total of 116 in 2007. With both Mussina and Pettitte quite possibly out after 2008, Chamberlain is going to be vital to the 2009 staff. If he doesn't get stretched out this season, they'd be taking a massive risk (in both a health and results sense) expecting 30 starts next year.
4. Mark Fidrych threw 250 IPs at age 21. He completed 77% of his starts. Apples to apples that ripened in a completely different era. (Also, Oswalt threw 175 innings at age 22.)