Not a local Utah board, but you could try
www.epicski.com and search their forums for keywords like Alta, Snowbasin, crowds, etc. You'll get tons of info, here's a sample thread:
http://forums.epicski.com/showthread.php?t=20084&highlight=alta+crowdsIf that fails to get exactly what you want, ask your questions in a forum post and you might get feedback from dozen or more Utah locals.
Your timing for your trip is about as good as it gets for tons of snow, Utah has received almost as much as the "once in a century" amounts California has been hit by since the start of the year, and probably dryer quality.