From Joe Klein at Time:
It was odd seeing John McCain without snark. I suspect his honorable, at times moving, and in some ways remarkable acceptance speech will be judged favorably by the public. It was a reminder of what he had once been as a politician ... and yet it did feel flat after the full-throttle bilge and vitriol of Sarah Palin and Rudy Giuliani the night before. It also seemed more a valedictory than an acceptance speech — more the end of a career than the beginning of a presidency.
... McCain's presence in our public life has been, on balance, a valuable thing. His speech tonight gave intimations of why that has been so, but it lacked the drive and creativity of a true presidential acceptance. He is the standard bearer of a failed ideology — ironically, a belief in "me first" before country — and tonight the leap between what McCain really cares about, and what his party really believes, proved too great a chasm for an old warrior to bridge.