i've always carried on my boots, just used the power straps and over the shoulder. that way i dont have to use a bigger bag to stuff them in and check, the extra weight of the boots is just more potential for higher charges (not to mention if they lose the bag...would suck).
i usually pack all my ski shit into my ski bag (pants, extra jackets, base layers, gloves, NOT goggles), then check a smaller bag for clothes for the vacation and then carry on a backpack with my laptop and my boots over my shoulder. i have never been hassled. i do the same as mentioned above, put my goggles in my boots so they dont get smashed anywhere.