I signed up for the text messaging feature, and it works. I remember when I looked at the directions that there was a way to add a custom note for a fuel-up. I have been searching this Fuelly website for at least 15 minutes now and I can't find ANYTHING regarding the use of text messages to record your fuel-up information. Has the information been pulled from the site or does someone need to "unhide" this information?
You can get to the SMS documentation here. Right now you can get to it from any page on the site in the lower-left corner. There's a note that says "Help uo test our new SMS fuel-up feature".
The feature is working out well, so we'll probably just add an entry to the FAQ about it. Sorry about the confusion.