Few network-play related suggestions
Here are my suggestions, after playing a few online rounds.
1) Currently if one player (or maybe even spectator) starts lagging, the whole game blocks. Since this is a turn-based game, this really shouldn't be necessary. Instead, if the player lags, make the game continue, and when his connection problems are fixed, simply fast-replay everything that happened up to that point. If a spectator lags, just ignore it, and fast-replay everything that has happened when he is back to normal.
2) If a player happens to drop/quit, his hedgehogs are still left on the map. How about just mass kamikaze-ing them in random directions, instead of confusingly keeping them on the map.
3) Does the lobby page refresh automatically? If it doesn't, maybe it should. Also, there should be some kind of indication as to whether a refresh is in progress/has happened, even if the refresh is instantaneous.
4) Display the player latency, just like the fps is displayed. That way the player knows if he is lagging, or someone else is.
5) If the player quits the playing field, he is back in the room. Have a button to get back in the field from the room.
6) Display the user name in parenthesis, next to the team name:
Killers (foo) #############
RDF (urandom) ##########
1) wrong, it lags only because of current player
2) a bit unfair imho
3) it does
4) ...
5) too hard to implement
unC0Rr ever the diplomat
HTML = How To Meet the Ladies
Here is my Unofficial Manual for HW. Hope you like it.
Still working on it. Don't worry. Will get it finished...Sometime in the future. 
could be. from what I've gathered from other people, previous versions didn't lag as much, though. that's why I assumed that it was not the case.
It's more of a comic relief, and kind of goes along with the style of the game. Maybe it could be considered unfair, but the directions are random, so it could balance itself with the rest of the universe somehow.
great. the suggestion for some sort of indication (accessibility++) still stands though
take for instance quake3-based games. they had a command to show a graph that displays the user's latency. though I'm not talking about an actual graph, just a number that indicates the current latency.
And now to continue the suggestions:
7) It seems that if the person that created a game leaves (due to him/her being the first one to die or something), the whole game stops. Would it be possible to continue with the game, instead of causing everyone to drop out.
I've never heard of a game that does that.
It's normal if the host leaves, all the others to drop out automatically. But it'll be nice indeed (if possible and if possible with not a lot of work involved in it 
).
HTML = How To Meet the Ladies
Here is my Unofficial Manual for HW. Hope you like it.
Still working on it. Don't worry. Will get it finished...Sometime in the future. 
I'm rather sure Blizzard's lobby based games (i.e. Diablo/Warcraft/Starcraft series) just passed the host role to the next player unless something major went wrong with more than one connection.
Regarding point 4 (lag display): How about just showing some small hedgehog disguised as a snake in the top left/right corner if either FPS and/or latency (to everyone else) is very low. But don't point out people lagging to others (imo that never ends well).
Isn't it a bit ridiculous to have 50KiB of effective protocol command per game and 1MiB of pings just to know you don't lag very much?
Broadband connection's for teh win ...
I'm not a big fan of Pascal etc. so I'm not quite sure how networking works in Hedgewars nor what data is exchanged but shouldn't there be some way to guess when packets are missing and/or falling behind or add a simple timestamp (or framecounter?) to one of the packets used for synchronization.
It doesn't have to show current latency etc. - it should just show you "eh, it's laggy/choppy and you're the reason". At least that's what I'd expect under that topic.