Dan I use to work in the Compton area many years ago, and about two years ago I was in Oakland and took a brief look at the street action. No Tijuana isn't as nearly as dangerous in my opinion.
In my case on the bridge it really wasn't anything, but I always remember reading Sir Brockton O'Toole's advice on TJ at the other World Sex guide, where he says:
"SAFETY ALERT: You may be tempted to save the cab fare and walk over the bridge into downtown TJ. THIS IS EXTREMELY DANGEROUS! The neighborhoods you must traverse are not exactly the nicest parts of TJ. And there are bandidos who lurk along this route who specialize in robbing unwary foreign pedestrians. Be safe not sorry. Pay $5 for the taxi. Ditto for your return to the border. Again, WALKING BETWEEN THE ZONA NORTE AND THE BORDER IS EXTREMELY DANGEROUS! Plain enough?"
In my case I walked many times to the zona, as it was part of my weigh loss work out, because after that walk and fucking at least two putas especially in the summer months, I'd lose at least 5 pounds from that one day, but usually only temporarily, as I walked a lot, and also walked to every bar over and over again, until I find someone I like.
However, twice in a roll I ran into a little trouble, or scare. Once these two guys tried to talk to me and I ignored them, they seemed to get a little upset and followed closely behind me, asking me to loan them some money, and calling me names, and at one point got a little bit close to me behind me, so I tried to let them pass, but they were determined to fuck with me, but nothing happen. The very next time I walked, there were three guys walking in front of me, and also 4 cops TJ Cops. They got the 3 guys, and seemed to be treating them a little rough as far as I could tell, and I just knew the forth cop was going to get me, and it was dark and no one else was around, but luckily for me, he let me pass. Usually I don't fear the cops, but in this case I felt they were up to no good, and I did have lots of money on me, more then usual, and I wanted to keep it.
After that I said to myself I better listen to Brockton O'Toole and just take a cab, especially since O Toole wrote the piece, Taxi Libre is around now, and if you can find one who turns on the meter the price is only $2 dollars for a ride to the zona.
The Bridge also has bums and I bet some homeless under it, and it's not a good idea to be hanging out there. During the day, and the summer months when it starts getting dark, the bridge is fairly safe, and there are lots of other people walking it, and the police are around, and not harassing the people, however when it gets really dark, very few people are walking the bridge, and that's when problems could occur.