Places open in Baltimore for Christmas Day? or Eve?
Many restaurants are open Christmas Eve, but tend to close a bit earlier then usual. Oregon Grill, Kali's Court, Prime Rib, Flemings, etc. are all good choices are places we've dined on the Eve.
As far a Christmas Day, you are pretty much stuck with hotel dining. Sotto Sopra is the exception.
Brighton's in the Hotel Intercontinental does have a lovely dinner and atmosphere. Hubby and I dined there last Christmas and plan to return. Yes, it is a hotel dining room, but we were quite pleased with our dinner selections.
One year we dined at the Prime Rib on Christmas Day, but they were only open because Christmas fell on a Saturday. So, this year they aren't open.
You may want to also check to see if the Milton Inn is open. I do believe that Joey Chiu's in the Greenspring Station will be open. FoiGras
If you're into Chinese food, you're in luck: most Chinese restaurants open for Christmas. However, if you're looking for fancier fare outside of hotels, the only ones I can think of are McCormick & Schmick's and Sotto Sopra. I personally am not a big fan of M&S, but I thought to pass along the info anyway. Still haven't made it to Sotto Sopra to try.