The following is a video advert from Yell that showcases their "Fly Around Your City" promo for their 3D maps. I'm not sure but I think "Fly Around Your City" is actually "Fly Around London".
That said; once you're on the London page you can access other cities from the left hand side but the numbers are limited. If you search for a city keep an eye on the top right to see whether the "3D city" button highlights.
The drag interface will be familiar to anyone who's used Bing Maps or Google Maps. I do like the way the whitespaces aren't square before they're filled in by the photograph though.
That's the crux of the issue isn't it; Yell are up against Google and Microsoft. Really not sure where they can go next. I think these maps are good. Yell's doing the right thing by drawing attention to them. It's just a hard fight.
What do you think? If Yell's maps where three times as good; would you use them?