I've been introduced to many delights by you chowhounds in the year or so since I moved to the Bay Area, but one of the best is xiao long bao. I have tried them in six places so far, and have rated them on the standard 1-4 star system (1 for fair, 2 for good, 3 for very good, 4 for outstanding). I'd be interested to know what your ratings are:
Su Hong (Palo Alto)
These are the best that I've had. The wrappers are thin yet unbroken, they are full of broth, and the filling is a delicious combination of pork and crabmeat. Eating these is truly sensual experience.
Shanghai East (San Mateo) and Shanghai Sichuan (Mountain View)
Both these places have excellent XLB, but the filling is just not quite as good as Su Hong's.
Happy Cafe (San Mateo) and Joy Luck (San Mateo)
Happy Cafe is very highly rated on this list, but I was disappointed with the XLB. The wrappers and the broth were perfect, but I didn't like the filling very much. It didn't have a lot of flavor, and it had the texture of hamburger meat, which I found unpleasant. Still, they weren't bad.
Joy Luck's XLB, OTOH, have a delicious filling, not unlike Su Hong's -- a mixture of pork and crabmeat. However, the wrappers were too thick, and some were broken and the broth had leaked out. Again, they were still pretty good, and they are available as part of the lunchtime dim sum.
New China Delight (Mountain View)
Overall, I like this restaurant, and it's probably the only place in downtown MV that has XLB, but they just weren't all that tasty and the wrappers were too thick.
I haven't yet tried some of the other places which have highly-rated XLB, such as Shanghai in Oakland (how similar are they to Shanghai East?), Shanghai Dumpling in Millbrae, or Old Shanghai in SF. I'd be interested to know how they compare.