Via Think Big Sacramento, the Urban Land Institute has released a report touting the feasibility and benefits of locating a new downtown entertainment and sports complex and a regional transit hub together in the Railyards. There are some challenges, the report notes, but if they can be solved, the outcome would have a serious benefit for not just downtown but also the surrounding areas.
The report emphasizes the idea of a compact footprint for the transit facilities (a high-speed rail/commuter rail station on the south side of the track, for example, closer to the entertainment complex and downtown). It notes that locating the transit facilities near the arena would provide some cost benefits and would allow for an attractive plaza or commercial building between the train station and the entrance to the complex.
There's also a big emphasis on pedestrian traffic and mass transit over regular auto traffic, which is something the downtown complex plan has a huge advantage over the current Natomas location. (Getting public transit to Power Balance Pavilion is like getting public transit to Mars. Walking there -- if you don't live in one of the nearby apartment complexes -- is about as fun as ... well, the 2008-09 Kings.)
Check out the report for yourself. Lots of interesting notes, if you're into land use at all.