The first time I went to Old Town Alexandria, I thought, “there needs to be a trolley along King Street from the Metro to the waterfront.” Well, now there is. Sorta. It’s really a bus dressed up as a trolley, which DC Metrocentric sneers at but I think has merit: a dinging trolley probably would be more appealing to visitors who shop at the high-end boutiques and chain stores on King.
A real trolley would be even better, but it’s a step. More prominent signage (or, rather, any prominent signage at all) would help a lot. This trolley/bus will run every 15 minutes, more than the bus it replaces, but 10 minutes would be better, as would real-time info displays. 15 minutes is a little long to wait standing on the street corner in the cold while deciding whether to walk to the Metro station or regret not just driving instead.
Update: more good discussion on DCist.