The city is putting up lights and decorations in preparation for Mardi Gras 2011. As you may or may not know, Mardi Gras is the feasting & partying in preparation of Lenten observances. I suppose if you make yourself sick enough of food & drink then giving it up will be easier. In theory anyway. OK, so now it's more of a secular winter celebration.
Given that we have a later Easter this year, likewise Mardi Gras will be later. The first parade rolls in early March, with the day before Ash Wednesday or "Fat Tuesday" falling on March 8th. Hopefully the later date will also bring warmer nights for parade watching.