Though, the interface in iMockups, and some of the color palette creators, seem more intuitive on the iPad.
I'll always do most of my work on my iMac, but having the capability to fix a small piece of CSS using textastic, and previewing it, is pretty powerful. Obviously editing something complex would be nearly impossible on an iPad, but for a simple web-page, or creating a small piece of a larger site on your lunch-break, the iPad seems like it handle that with flying colors.
Do no other web professionals push its practicality within the office?