My family and I went to the TNF game at Seattle last season. But because we arrived on Thursday morning (and it was our first visit there), we didn't get a good lay of the land to determine where Rams fans meet up for pre-game. We DID, however, see several Rams fans at the various local restaurants in the downtown area.
I will note, though, that that TNF game was Week 6 (early October) and we enjoyed really good Seattle weather (i.e. low 60's with only one 4-hour period of rain for the 4 days we were there). So, people were out an about that whole weekend flying their colors (more Rams fans, though, because we smashed them and knocked Wilson out of the game). Not so sure what things will be like in early January, though. I'm sure it'll be freezing and I don't do freezing.
But if you have good weather, you'll have a great time.
