Just a couple of other points about the draft which might be of interest to fans:
1. Many teams make a draft list of only 80-120 players for the draft. This means that a lot of players that ranking services and casual fans might have placed in the 2nd (and even 1st) round might not even be on some teams' lists.
The logic behind this is my 2nd point:
2. Most NHL (I'm making an educated guess here) want a list of players who their scouts think CAN EVENTUALLY PLAY IN THE NHL. This is very different from a "list of best players" ranking.
For example, let's say there's player X, a center, 1987 birthdate, in the OHL, 6'0 180, who scored 20 goals and 25 assists in 70 games, a decent two-way guy with some grit but no outstanding feature. Just looking at this, he might a decent 4th or 5th round prospect. But if the scouts just cannot project him as a future NHLer, instead a good AHLer or Euro-pro then he simply won't even be on their list. I've seen lists where projected 1st rounders (according to Redline, ISS etc.) are not on an NHL team's list at all.
Most teams (again, a pretty educated guess) would prefer to spend a pick on say, player Y, an AJHL guy with one or two enticing attributes, who hasn't had too much exposure, but with 4 years to develop in college, it is POSSIBLE (according to scouts) that he could contribute AT THE NHL LEVEL somewhere down the line. So, despite the fact that the OHL player X looks like the better prospect to many fans and ratings agencies (and maybe even another NHL team or two), that NHL team will have player Y rated much higher on their list.
This is why, say, relatively unknown Andrew Kozek goes in the 2nd round while WJC regular Risto Korhonen goes in the late 5th. The consensus must be that Korhonen will not go beyond being a good pro in Finland even though most NHL GMs would probably choose Korhonen over Kozek if picking sides for a game tomorrow.
And, by the way, I've never heard of a case where every player on a team's list - even with only 100 players- has been chosen.