If you switch to first person mode while spectating people (Behindview 0 in console, when it's enabled on the server) some strange things happen.
Each player is missing their HUD (only displays their name and gun), likewise their weapon either displays 000 or 999 for ammo (I notice that weapon models also seem to display the numbers 999 in third person view, but perhaps this was just a shortcut designed to save memory.. but the first person thing is kinda strange). Also the projectiles from the guns in first person are missing (you see the explosions and impact hits on walls and bodies, but not the projectiles and bullets).
While right now this is not too big a deal (just looks funny) if/when we are able to start recording demos of this game, the normal UT way, then we'll be forced to use third person mode only, because First Person is so messed up.
I also think it's annoying that you can only view independently from one camera (or view directly from each player's view). In Q3 engine games you can "break away" from a player at any time and wander around the map. It would be nice if you could do that here. The independent camera is cool, but rarely is it where you want it to be while viewing.
Being able to view the health and stuff of various people while watching a demo would be nice for learning tips and for more suspense and to see how well someone really did.
Also, not being able to kick/ban people is a major problem, as we've had some people trying to disrupt games on purpose (team games). In deathmatch it's not really a problem, but in all team games there's huge potential for abuse without basic admin control over the server. We can't even change settings on the fly either.
Those aren't bugs, but major oversights. These are things that they will hopefully fix in the first patch soon. If not, online gameplay will seriously suffer. This is stuff that should have been included on release day!