I just got back from London with my family of 4 (I was there 2 weeks, they stayed 3) and I want to say what a wonderful time we had. The mass transit system is great (and almost always on time), our flat was nicely placed (North Kensington, leased through London Guest Suites), the weather was better than I had expected.
I know people get jaded about their own town; I just thought you'd like to hear some nice things. Here are my thoughts:
1. The best jazz I've heard in years; better than anywhere in the US (outside of maybe NYC and New Orleans). I wandered into a pub in Isleworth and found myself listening to a jazz drummer that had worked in NYC with Martha Graham, and he was backing a sax player that had played with many of the greats; the music was as good as I've heard anywhere (and I'm a professional musician)
2. clean city and someone offered to help me every time I needed it (you have to ask though);
3. amazing selection of -- um, beer and ale-type libations (and normally I don't drink)
4. great food, though pricey
5. great theatre, rivals anywhere in the world
6. the diversity is awesome; I've never shared space with so many people from so many different places
7. To an American, the history is overwhelming and thrilling
8. a great walking town; if you don't know what to do, just get into town and start walking, you'll run into amazing sight after amazing sight
9. Great musuems (and free!); the Tate Modern is a quality addition
10. outdoor markets with a very big "wow" factor
11. I even rented a car and drove (don't recommend it, but I'll never forget it)
In short, though I'll be paying for this trip for quite some time, I will remember it much longer than that.