After staying in Athens for a few days, I find the majority of the guide books to be wrong. Their advice was this: see the acropolis, see the museum of archeology, get out. Their out-dated advice called the city poluted and nasty.
As I understand it, the 2004 olympics was a turning point for the city. Many projects got underway and cleaned up many of the areas that were previously ugly. One of the guidebooks said, "forget about the rest of Athens and just pretend the Acropolis and Plaka district are all that there is in the city". I have two points here: 1) If all my city has was the Acropolis and the Plaka district I think it would be pretty fantastic. 2) This city has much more than just that. It's pretty spread out but just speaking of the city center, there are some gorgeous/fantastic areas including the national gardens, constitution square, and an ultra-modern business district that can rival a lot of big cities in the US for style and architecture. Not to mention a plethora of cool museums.
Being here longer than the guide-book recomended, two days I have to say that I've enjoyed this city at least as much as Rome. I don't know if I'm biased because I'm sitting on my balcony while typing this and turning my head to the right I can see the Parthenon perched on the Acropolis with its huge columns lit from below by spot lights. Uh, awesome...
Don't get me wrong though, there are areas here in Athens that I wouldn't pass through with a swat team but isn't that true of every big city? Generally, when I'm in Miami and driving to the beautiful Coconut Grove area I consider a red-light at the intersection of Douglas and Grand to be more of a suggestion than a hard rule. :)