From the Ashes of Angels
XP is split evenly among the player characters, whether they are present for the session or not. XP totals of present characters are brought up to the current party total at the end of each session. This means that a player who misses one or more games will be down xp relative to other characters on the first session he returns for, but will be caught up in full at the end of that session.
I will not require an extended (or even short) rest for advancing in level. If your end of game xp award pushes you over a level threshold, come to the next game with the next level version of your character. This is admittedly a concession for ease of bookkeeping, but I’m happy with it.
I intend to award XP for anything that adds to the game experience. From time to time I may even post some OOC quests on the wiki (or announce them at games). Generally these quests will only be accomplished by a single player, but the reward will still be shared among that party.