I was originally planning on writing about misunderstood features like "Followers / Following" and the account migration, but krosan already covered this in his article.

So instead I'll talk about features that I personally like.

Notifications


They do all of the work that was usually done by private messages by the crossfire bot. In my opinion they're a lot more comfortable and intuitive. They pop up right on the page without being "in your face", they don't stick around to annoy you when you followed the link they presented to you but inconspicuously disappear (in most cases). The polling interval for this was reduced compared to cf3, so you'll get those notifications quicker than before and of course you don't have to click 3 times to get to wherever they're sending you.
I have two suggestions which would make them even better:
1st) Make them "sticky" - if you scroll down below the point where they're "anchored" to the messages symbol; detach them and make them stay in your viewport until you scroll back up.
2nd) I often have pages like crossfire idling in a tab without really checking it that often. It would be nice to have the favicon change when you have new notifications:
image: Screenshot_from_2012-07-16_202801
How about something with a flag in it?
3rd) I'll mention it even though I don't really like it, but I think some of you want it: A simple sound notification when you receive a message. With some cheating and using bleeding edge browser technologies it might just be possible to only play that sound when no crossfire tab is currently in the foreground.

Recent content


... on the right, just under the header. I really dislike the auto-rotating between the other two (useless) tabs, but in my defence: I objected to that from the beginning. Judging from your whine I guess I was right about that.
But the recent content - I love it and I think it's greatly underrepresented, it deserves its own big section!
Crossfire consists of so many different sections that it can be hard to keep track of all the new posts, the longer you're away the harder it gets and even when you're active it is annoying to have to check every section on its own.
This is something that shoule be extended. It should be a link to a new page with one great paginated list showing all the content every posted in reverse order. Probably even better than classical pagination (new page every x items) would be a pagination by date - combined with a simple url format this can be powerful, imagine: www.crossfire.nu/posted/2012/07/16 - showing all content that was posted that day.
This can be extended into the impossible of course; highlight topics that you never visited, or which have new comments since you last read it. Highlight stuff that (for the time it was posted) has exceptionally many hits and/or comments. I see a lot of potential there.

The logs


What? Yer, the logs.
This might be hard to convey, but clever logging is not a nice admin tool to annoy and track you beyond all believe. It's quite the opposite. Imagine you put a lot of time and effort into contributing content and suddenly it disappears without notice. This is an issue that was improved on the late cf3, but I still remember discussions about who did what and why. I can even remember server admins going through access log trying to pinpoint the source of such an action. With proper logging this is a non-issue. Finding out who did it is a matter of seconds. It might seem strange that I write about this part of the page that will never ever be seen by most of you...but why not?
This idea might not be popular with admins, but I can imagine some of them playing along: They could opt-in to allow their administrative actions to be tracked by regular users because despite popular believe, most of them do a good and fair job.
Also, your own logs could be opened up to you. This might seem useless, but maybe some day you'd like to know what you did that other week 3 years ago ;) I won't post screenshots since that panel is not quite where I want it to be (layout wise, functionality is there), but that's something can be tackled in the future.


I'm writing this in the big hope that you can see the potential that exists in many of the currently rather basic features and that you can get as excited as me about the possibility we have in shaping this page to all our likings.