I started last Sunday with SCAP... a very mixed group, some totally new players, who gave ablility scores to their characters "just because they want to play a smart character" and some hardcore gamers who spend days of min-maxing on their build, looking for prestige classes and walking the edges of what they thougt i'd allow as DM :) I wonder how it works out...
In the end, I ended up with the next 7 players (7 because the hardcover advised 6, I like to DM big groups and cause it's not unusual 1 person can't make it for a session): HE druid, HE rogue, dwarf monk, dwarf ranger, human paladin, gray elf wiz (evoker) and gnome cleric.
I gave the characters the following info to start with: they had to play all young folks, for their race. All of them are natives of Cauldron. Last winter, they participated in the games on the flood festivals, and each won one of the games played there (archery, grappling, or some skill) in the 'youth contest'. They all won something, got to know each other in that way and got befriended, as a group. In the past 3/4 of a year, they hanged out, and recently got the idea to start adventuring together; cause of the general lack of adventurers in Cauldron, cause their abilities stack pretty well and cause they are all pretty "above average" in their fields (next to the very generous character creation system that SCAP recommends, they rolled bloody good!).
With this info, it's up to them to create now a character background, family history etc. They can decide whether they want to have family, live all their lives in the city, are brother/sister/having an afair with a party member, etc.
The first session I had started in the "tipped tankard", 'the tavern they usually hang out'. I told them about the recent dissapearences and that they figured out it would be a nice start for ther adventuring carreer... and that was the beginning.
Advantages of this start: all of the players have to play natives, they are already familiar with some of the locations and events that are bound to return (flood festival, tipped tankard, the lack of advanturers in Cauldron although they don't know why). Also, the barman of the tipped tankard is one of the missing persons, which is and extra drive (and I asked my players if one of them occasionally visits prostitutes... when one confirmed, I told him that his favorite prossy dissapeard about three months ago, but I can imagine this is not an adventurehook to use in every game).
First session was about 6 hours playing time, ended just after getting info out of Keyghan and just before entering Jzadirune. What cost my players the most time was not solving the riddle, but what to do with Keygan, since they strongly suspected him pretty early in the session but couldn't really figure out and agree on what the best way was to get more info out of him.