Comfort was the biggest thing for me because I'm not very flexible (but I'll get there!) so I was a little timid in getting started because I didn't want to look like a fool. I'm so glad that I jumped in and got started because once I got there I didn't even think about being a newbie, I wasn't the only one and I could get through the class at my own pace without feeling weird or like I didn't know what I was doing. Well I shouldn't really say that because I still didn't know what I was doing but it wasn't difficult to catch on; the movements weren't like you probably are imaging (people bent into pretzels...).
Give yoga a shot, you'll love it!