They are now! In fact, as of August 2007: TSA: New Policies for Lighters, Electronics, and Breast MilkAll lighters are no longer allowed in the sterile area (Beyond the Checkpoint)
Honestly, in April 2007 my lighter was confiscated when I went back through security at Newark, so I got bookmatches for the flight home. I took the same precaution Feb 2008, not knowing lighters were OK again. Then I heard they were OK, and last November I cleared security at Orlando, Atlanta and Newark (several times) with a lighter in my bag no problems. I guess the ban lift wasn't that well publicised as I spotted many, many discarded lighters near the checkpoint in Atlanta!
I will be sure to take my e-liquid in its original bottle, I was gonna take it in a smaller, plain bottle but I'll heed your comments, thanks