Let me start off by saying I like this a hell of a lot better than the default widget.
From the get go on the Home screen it *feel* and looks like Facebook. On my N97. Top marks for giving that first impression. Given the early state it is in, I couldn't quite try out more features that I normally use in Facebook but I'd thought I'd list down a couple of things as a suggestion:

1. Update Status - Goes to my wall feed? My friends think I'm nuts. Shouldn't it update *the* status?

2. Offline mode - Would be nice if there's a little option to disconnect from the network like the email client does, not a real want item.

3. Change profile photo - If we can upload a photo can we use this to set our profile picture?

4. Installation location - Can we have the option to select a location other than C:\ ?

5. Responsiveness of the application while typing - Can it be a little more responsive? Felt a little laggy when typing things in the app.

6. Facebook chat/friend status - Most other FB apps don't have this (AFAIK). Possible to have this?

That's all for now, probably post a little more when a new release comes in.

18/12/2009 - Update
I saw on OVI that a update to Nokia Messaging was available. I downloaded it and I'm pretty pleased with it so far:

1. Clean interface - It's a lot neater and organized. The front widget is pretty nice as well, you can scroll down to your feed using it. Not sure how you guys squeezed a scroll bar there :D

2. Nice to see the installation destination is selectable.

3. Did not feel sluggish while typing. I supposed this could be chalked to the fact that it isn't sitting on 'C:\' anymore.

One issue though, occasionally I get a 'Client couldn't connect to gateway'. Rebooting usually fixes it - if this helps anyone.

My thanks to the team, it's nice to know the improvements are rolling in :P