Vancouver is grand. Best thing about the city is the layout. Unlike most cities, when 6:00pm rolls around the downtown doesn't turn into a ghost town. Commerical, Residential, and Entertainment are all mixed together so every street has something going on. As well, the Skytrain service is excellent to get to the major destinations.
I hope the weather gets its ass in gear though. It has been dark and cold the last month. Though when the sun does break through the clouds the temperature jumps about 15 degrees celcius!
Stay the hell away from the East Hastings part of town. That is where all the heroine and crack addicts are and the place is just a fucking nightmare. Dirty needles and fucking degenerates are everywhere. Chinatown is right on the fringe of this part of town. Sure it has a newly built heritage gate and the Chinese Gardens which are nice, but the rest of it is pretty weak. Though, the best multiplex in downtown, Tinseltown, is right beside Chinatown so if you go see a movie you can take a look.
Best thing about being in Canada though is even in the worst part of town the chances of someone pulling a gun is pretty slight.
Like others said, you want China, go to Richmond. It is like a new, clean, lowrise version of Hong Kong.
Otherwise, downtown has some ok beaches, nice swimming pools, good hotels, brilliant sea wall, fantastic parks, amazing restaurants, etc. Good sushi is everywhere and it is pretty cheap too.