Selig is no surprise, of course. Every commissioner with more than a single term tenure has been elected. The MLB article makes it sound like this is a rare accomplishment ("...just the fifth (commissioner elected)...," "...only the second Commissioner inducted in the last 25 years..."). Selig was the only commissioner for most of those 25 years. It was inevitable that he'd get in.
Schuerholz may not have been a surprise, but it may be surprising that he was a unanimous choice. There aren't many executives in the Hall, but it seems that with Gillick being elected a few years ago, maybe more will get in.
The players on the ballot really weren't deserving, and none of them got close to being elected. Some of them were just off the ballot recently (last year for McGwire). It's puzzling to me why they should be voted on again so soon. What do we know now about them that we didn't know last year, or the year before?
Two managers also failed to get the votes, Davey Johnson and Lou Piniella. Both managed one world champion, and if memory servers neither one even had one other league pennant winner. Most of the managers in the Hall of Fame with only won championship were perennial contenders with several more World Series appearances (Bobby Cox and Earl Weaver come to mind). If Piniella got in, they might as well put Joe Maddon in right now, since both of Maddon's teams were bad under Piniella shortly before Maddon took over.