Best way to update to latest versions of custom ROMs? What is the easiest and most time effective way to update to different builds of a custom ROM ? 
Say for example, having an Infuse, I follow the builds of Cyanaogenmod 10 and they release updates every week or so. What I usually do is to use Titanium back up pro to backup my apps, flash ROM and do a restore. (which of course takes a lot of time)

Is there a better way to do this that I'm not aware of ? Does updating to a latest version need to have the same steps as flashing a new ROM entirely ?
If you upgrade your CM10 to a newer build of CM10 you can just flash it right over the existing one, and you are ready. There is no need to backup all of your apps.

The newest builds of CyanogenMod have an updating system build-in however so you don't have to do it all by yourself. It is under System Settings - About Phone. It still downloads the complete zip of the newer build but handles the updating by itself.

There is, however, a new method to update your CyanogenMod. CyanDelta is an app that calculates the difference between your build and the newest build and will only download and update this difference.