I can't really comment specifically on Edinburgh's proposed service but what I can say is that most of the opinions being voiced on this thread I heard time and again by people here in Nottingham (myself included) before our system was built.
Now people love them.
Yes, it was a pain while the roads were being dug up. The route is fairly restricted too (I rarely find a use for it personally). Everyone said it would be a waste of money, dangerous, interfere with traffic etc.
The result is full trams all day with standing room only in busy periods and TWO proposed brand new routes. People like them because they're reasonably cheap, efficient, reliable, regular and comfortable. Another factor is that people like them because they're safe. Having a conductor helps in this respect.
Friends of mine have even had good nights doing the 'tram pub crawl' hopping on and off on a night out.
http://www.thetram.net/
Have a trip on the Nottingham Tram. It does 500mph!
http://www.bbc.co.uk/nottingham/feat..._journey.shtml