It'll reopen when they fix the problem...
Due to electrical problems, Davis Station will be closed from the start of service today Tuesday April 4, 2006 and will remain closed until repairs are made. North and southbound train service will by-pass Davis Square Station. Supplemental bus service will run between Davis and Porter.http://www.mbta.com/traveling_t/transitupdates.asp
Passengers seeking Red Line train service from Davis Square Station must board shuttle buses to Porter for all Red Line train service.
Passengers seeking Red Line train service to Davis Square Station must board shuttle buses at Porter.
So, if walking to Porter or Alewife makes sense to you, I recommend it. That is my plan, thanks to a phone call from the lovely unequilibrated.