Being the most informative member, in my mind, means that you actually have to
get your information across. That is, of course, after you a) have information people actually care about and b) try to communicate it in the first place.
That basically leaves this as a two horse race between Loony BoB and Rantzien. Let me tell you what has excluded the other nominees first and foremost.
crono_logical - Crono doesn't really post that much. I mean, don't get me wrong, I'm glad he's come
back in time 
for the Ciddies, but being the new Christmas doesn't really qualify you as "informative".
Iceglow - As part of a campaign to try and help the forum tackle Iceglow's posts, I recently started culling his posts at 50 words. That was a whole lot of effort, and ShlupQuack's suggestion to "sum it up in 5 words" was just as much hard work. It's a lonely world, being one of only two people who actually read Iceglow's posts (the second being his mother).
o_O - I would listen to everything he has to say if he does it just like
this.
Wolf Kanno - Wolf Kanno is a lot like Iceglow without the references to your mother. Now let me explain before he stabs me. His posts are
long and often contain
good information, just not presented in a way that encourages people to read them (refer to the part where they are
long). However he does make shorter posts occasionally which might actually put him in with a shot.
Yeargdribble - Posting primarily in EoEO is not good for you either because the only people who read your posts are people who want to argue with you and rip out your spleen. Not necessarily in that order either. I don't spend much time in EoEO either.
The other two - Do they post things that anyone else is interested in? Well that's for you to decide. I know I read their posts because they are bite sized and
informative.