I ended up booking for Vancouver! I was really leaning towards SF, but other people convinced me otherwise.
So thank you guys for all your suggestions.
Vancouver after all eh... I just went there a couple years ago so I'll toss out some suggstions...
Food- Enjoy the seafood if it's your thing because it's awesome. Also they have a really big Asian culture and population there and probably some of the best Asian cuisine in all of North America.
Shopping- If it's your thing or going with someone who enjoy's it you have to go to Robson Street.
Wreck Beach - This might be a shade too cold in May but it's one fo the nicest and most scenic beaches in the Western part of Canada. Fair warning that is in fact a clothing optional beach though and probably has some "interesting" characters. So one good thing about it being cold in May there's far less chance of seeing some fat 75 year old dude wearing nothing but sandals...
Harrison Hot Springs - A beautiful locale mostly on the water, can easily spend most of a day there.
TV shows - They actually film alot of TV shows in Vancouver. I doubt it's filming season now but you never know...
Victoria- Actually the capital but is another nice place on the outer edge. Beacon Hill Park is super nice.
Sunshine Coast - If you like the outdoors this place if awesome. Has cool beaches and great hiking trails both through the woods and along the actual cost. I'm pretty sure you can only get there by ferry though. At least I did.