First of all, from a marketing point of view, a great twilight exterior shot is the single most valuable photo that you can have on a listing.
Steve Pacinelli argues that a twilight thumbnail on a listing site will increase the online visits a listing will get. I can tell you for sure from direct experience a twilight shot will bring the listing agent more listings. We've gotten several listings solely because the home owner saw our twilight shot on our listing, website or flyer and wanted one for their home.
My feedback for Joanna on her twilight shot (click on the photo above to see a larger size) is that I would work at controlling the exterior lights on the home. This happens to me all the time. The exterior lights on the lower level and the deck level (where the red arrows are pointing) are too bright and distract. The ones on the lower level could easily be just turned off with no loss. The yard light in the foreground is a distraction too. Same for the 5 or 6 big lights along the top of the railing on the deck. Another option would be to take an exposure with just the deck lights (all other lights off) and then bring in the those bright lights into Photoshop on a separate layer so the intensity can be controlled with the layer opacity.
Shooting tethered can help you spot these distractions right on site. It's frequently difficult to notice these kind of distractions in a small LCD screen on your camera.
I think watching Mike Kelley's excellent video tutorial on shooting a layered twilight shot is a great way to start thinking about twilight shots where various areas are on different layers. If you shoot different groups of lights on a separate shot you can then easily control their intensity. Mike's example is much more elaborate where he's lighting with a flash but the same approach could be used here if you wanted to keep the exterior lights on but bring down their intensity. In this case, a quick and easy solution would be to try a shot with the exterior lights off. Some times you can run around and just unscrew some bulbs to save time in finding all the switches. The best solution is of course having the home owner there to run the light switches for you.
Anyone else want to give Joanna feedback on her shot?