Taos and The Bird-fun mountains to compare-snowbird has the least really good beginner terrain of any mountain I've skied on...except one, and that one is TAOS! Snowbird also gets way more (and much more consistent) snow than taos, which helps smooth out the rough spots (Taos, aside from being impressively steep in every direction, also required more 'quick-stepping around pointy rocks' than anywhere I've been to...I love Taos, mind you, but it has quite a bit of rigor associated with skiing it well.
What other folks said about Alta is good advice, there's quite a bit more for beginners to enjoy over there and it is literally right next to Snowbird.
General Comparisons: At Snowbird, the best steeps do not require hiking...there is no equivalent to Kachina Peak! The steeps get open sooner at snowbird and stay open longer. There's more hustling at snowbird, Taos allows a more laid-back approach to getting the goods in a day of skiing. Taos is on average way sunnier. SLC and Sandy are no substitutes for taos (the town) and Sante Fe!
When both are covered in snow and everything is skiable (and yes I realize this is the case much more at snowbird than at Taos) I think Taos is a slightly better mountain...but only for 2.5 weeks out of every two years (last year was a pretty good year at Taos, right? ask locals about the year before, 30 inches...for the season!)
Anyway-you'll love Alta and The Bird just like everyone else-and If you spent a season at Taos, you'll be well prepared to get the most out those mountains as well.