Now that it's over, here are my thoughts.
I have lived in Basel for 15 years, but both DH and I are immigrants. DD17 and I were lucky to get tickets for the afternoon run through of the 1st semifinal and I also won 2 tickets for the public viewing of the finals in the football stadium (DH and DD attended).
I am European (Croatian) and I watched the ESC growing up, but not much as an adult. Now, though, as it was taking place right here, we all followed it quite closely. Basel is a relatively small city and quite international, you routinely hear English, French and many other languages living here (~35% of the population are foreign born).
The first semi ended up being the most entertaining, in my opinion. I liked "Made in Switzerland" very much. As a non-Swiss, I thought Sandra Studer (the moderator who competed in the ESC) was great, Hazel Brugger was definitely not my cup of tea and didn't get better in the three shows.
The atmosphere in the city was nice! I was worried we might have issues with getting to work/school, but those were unfounded. As far as I know, there were not many security issues, either. There was a pro-Palestine demo during the finals yesterday; in the end, the police dealt with it with restraint, and while there were some injuries (3 policemen, don't know how many protesters), they managed to allow protest while not crippling the city and the competition, unlike Malmö last year.
DD and DH had a great time at the public viewing (36,000 people in the stadium, a fun pre-show with Baby Lasagna, among others, and a public choir singing Waterloo). I stayed home and watched it on tv.
My votes went to Albania, Latvia, Austria and Norway. I was glad to see that all of them did ok. The best singers, in my opinion, were Austria, Greece, France. Yuval Raphael also has a good voice, as does Zoë Më for Switzerland (it's sad she got no public votes, but I'm happy she was rewarded by the juries).
The highlight for me was the Baby Lasagna/Käärijä mashup! However, I'm not objective (see: being Croatian).