Uncle Mo's late scratch from contention from the 2011 Kentucky Derby left the race without one of its few clear favorites and strengthened considerably Dialed In's position as the last juggernaut standing in a relatively wide-open field, but since Uncle Mo's disappointing lead-up to the derby and subsequent exit there's no longer any dominant horse preparing to run away with things.
The New Jersey Star-Ledger likes Dialed In, for instance—considers him "the best horse in the race"—but concedes that things will still need to break right for him to pull away in a crowded field of horses, many of which have their own possible advantages. Each of their predictors has his own second-place winner—Archarcharch, for his closing ability; Nehro, for his continual improvement; Stantiva, for his flexibility in an uncertain environment.
All that rationalization makes it clear that nobody's quite sure what will happen in the 137th Kentucky Derby, which isn't especially unusual. The difference between this year and years past is that most people aren't even pretending they're quite sure any more.