I often find satisfaction in the desecration of sacred cows. When it comes to pop culture, "Imagine" is indubitably one of the most sacred. With that in mind...
From The Daily Dish's Andrew Sullivan:
Personally, I have extremely mixed feelings about this song. Most times it makes me want to vomit because of its self-serving sanctimony and silliness. I mean: Lennon did not have to imagine, he could have sold every thing he owned to the poor as Jesus recommended to the rich young man. But life in the Dakota was somehow preferable. But I must confess that occasionally - if heard purely as a utopian fantasy - it can work. Musically, it's sublime. And then you hear David Archuleta's version and you're back to cleaning the puke off your laptop.
From one of Sullivan's readers:
Regarding the “I wonder if you can" line in the song, when Neil Young performed it at the concert to honor the victims of 9/11, he changed the line to “I wonder if I can?” Not so sanctimonious that way, but rather a humble challenge to himself. That one word changes the whole song.