Thank you Bob. What do you mean by signature shots in my work? Yes I did use a Cable release on my photos
"Signature" might not be the right word, possibly "iconic" would be a better choice.
In any case, what I meant is shots that are instantly recognizable, and immediately establish your location and your skill. (While night shots are actually fairly easy once you master the technique, they're also quite impressive.)
When you show somebody your portfolio with shots like that one in it, they'll hopefully react with two thoughts: that you're in Seattle and that you're a really good photographer.
As for the cable release, I thought so. The bright red lights on top of the buildings are a give-away. If you just press the shutter with your camera on the tripod, you often get a small bit of shake. That won't show in most of the image since it happens so fast, but those little red lights are bright, so they often show the motion.
To combat the problem, either use a cable release, as you did (the best approach), or use your camera's self timer so that the vibrations damp down before the shutter releases. If you camera has one, and you're really serious about no movement, also use a mirror lockup, though that's usually overkill unless you're shooting with a really long lens.
