From what I've found on my various searches, the primary election schedule stays the same as before (i.e. 2004), but between now and then we'll see various state-level legislation to change them all around. So far I found the following changes:
- Arkansas: Primary to be moved from May to first Tuesday in February.
- California: Apparently due to record low turnout in the 2004 primary, it will be moved back from March to June.
- Minnesota: Precinct caucuses to move from first Tuesday in March to third Tuesday in February, to coincide with neighboring Wisconsin. Primary to move from September to June. These measures have not yet passed, however.
- Pennsylvania: Ed Rendell has expressed interest in moving the primary from late April to late January or early February.
- Western states: Bill Richardson has promoted the idea of grouping the Western state primaries early in the primary calendar.
As for Oklahoma, it looks like it'll stay part of a 'super Tuesday' for now, unless it changes before then.