DISCLAIMER: This is more of a sorta-informational, sorta-rant post.
Responsive design has been made possible with the media queries that CSS3 brought, and it's super awesome that you can make your design shift to the screen size that you're using instead of having a mobile site and having to design a separate mobile site entirely.
Personally, I don't like to make designs responsive because it takes so freakin' long to override all of the styles that you had originally put in place for the design to work on a normal screen. Once you start to get to smaller screens, all of your custom-width items have to be resized instead of just having a cascading effect to fix those when using a percentage width.
The one big thing about mobile design is touch interactivity. Hover events no longer have their splendor or functionality, so if your site depends on any sort of hover event, you'll have to think of a workaround for that particular functionality. There are some things that open new possibilities with touch devices, such as a long tap, double tap, slide, etc to replace some of the missing functionality that your desktop version may have.
I like CSS frameworks like Twitter's bootstrap because it's already all ready to go with widths and responsiveness. Column grids are fantastic if they're responsive.
What are your thoughts on responsive design?
