What are you interested in?How do you like your resorts? What's important? Terrain, weather, snow quality, dining/nightlife, lodging, access, cost, crowds, type of group/family, time of year, etc. That said, from the perspective of someone who has skied W-B over 25 days over the course of 6-7 years (usually in late January), and skied Squaw countless times, here are some discussion points:
W-B: huge, lots of steeps, lots of variety, although the marked part of the bottom 2K of 5K elevation is usually frequented by Gumbys on crummy snow. After 25+ days, still have plenty to explore.
Squaw: smaller in size than W-B, but lots of steeps. there are lots of lines to take off the same chair that give you a much different experience. skis bigger than acreage. can feel limited to an intermediate lacking in adventurous spirit
W-B: can have bad visibility days and/or rain days. Most of my days there have had some vis issue somewhere on the mountain. 3-4 of 25 days pretty much had rain top to bottom. Have also had incredible pow days.
Squaw: Generally much better than W-B, except for high wind days.
W-B: some years had nice cold pow, most years had coastal snow, one year had crummy snow & rain in late Jan.
Squaw: the term sierra cement means coastal snow; but that's better than you'd think. usually at least as good, if not better than W-B due to elevation/exposure
W-B: fantastic if you're young, excellent otherwise, don't know about family choices
Squaw: getting better with village; otherwise you have to drive to Tahoe City or Truckee. W-B has big advantage here.
W-B: lots of it, and big range in prices/locations/quality. Advantage W-B
Squaw: not that much near hill; see, Truckee/Tahoe City
W-B: Beautiful 2.5 hour drive from YVR; depending on size of group, may/may not want to rent car v. take shuttle. Have to go through customs.
Squaw: 45 mins from Reno, 3.5 hours from SFO (depending on time of day; could be 5 hours in traffic).
W-B: not that cheap anymore
Squaw: never was cheap
W-B: Have been in 20 minute lineups at Harmony, for example. also, has bottleneck areas, i.e. Excelerator on Blackcomb to slow you from getting to higher elevations.
Squaw: lots of high speed lifts move people better, but there are a lot of people. Advantage Squaw.
Hope that helps a little...