Now I walk there all the time. I've never had a problem even late at night. Pretty crazy. My GF walks down Mt. Vernon from work by herself all the time.
I've even walked from Drexel, along the river at like 2 am and didn't have any problems.
That being said, it is winter and muggers probably don't need to freeze their dicks off.
When I told the cops where it happened they were pretty surprised. Just shit luck for me I guess.