My take is that the lineup for last years festival was fab for the first day and stinky for the second... Were it not for the brutally hot weather and being UNDERWHELMED by the Police at Bonnaroo, it would have been worth my while to get a one day VIP pass for that one day.
Personally, I'd been more interest in a festival with two medium size stages with the type of acts that typically play the 9:30 club or auditoriums. Just not that interested in most arena level acts these days. The best part of the first Vfest was the vibe at the second stage, people hanging out, listening to music and not crammed in like sardines. Totally opposite to what the conditions were around the main stage.
Bonnaroo for me was a cool experience because I could easily wander between the smaller stages and catch parts of several bands sets. The open air tent structures were nice as well for this festival..