I was born & raised in Calgary so I've been to the zoo many times - however, not as much recently and it's changed a lot since I was a kid. I was especially surprised during my latest visit when I found out that they don't have polar bears anymore.
This year, I visited for both Zoolights towards the end of 2011 and a regular zoo visit in the first week of 2012. I especially had fun taking pictures of and tweeting the animals as we wandered around during the 2nd visit.
The zoo isn't quite as pretty or exciting in the winter, but still pretty cool. Merchandise (and food) is expensive and it's reaaaaaally disappointing how many food vendors aren't open in the winter (I just needed a coffee!)
All in all, though, it's good exercise walking around, the kids love it and if you can find coupons (or have an annual pass) it's not *too* expensive an activity.
(Yelp Kicks Butt Challenge 8/10)