Well, I kinda understand the main reason for this topic. And I agree with it in part but I also have to disagree.
For instance, we can't say that there aren't big bands in the bill, aswell as good ones. We have Amon Amarth, Heaven & Hell, Machine Head, Motörhead, Napalm Death and Testament, bands that are 'big' in the metal scene.
On the other hand, when we compare this lineup with other years we see it is short for this time of season (globaly), and very short in a lot genres! Just as an example, I will list the first bands of two Spannish Metal Festivals.
Lorca Rock Festival, Spain - July 24/25
Akercocke
Arch Enemy
Carcass
Dark Funeral
Evile
Marduk
Meshuggah
Municipal Waste
Obituary
Pestilance
Metalway Festival, Spain - June 21/22 & June 26/27
Amon Amarth
Blind Guardian
Dark Tranquillity
Destruction
Epica
Europe
Heaven & Hell
Immortal
Manowar
Moonspell
Motörhead
Primal Fear
Stratovarius
Tesla
First of all, I think everyone agrees that both of them have superb line-ups, with renown bands in most metal sub-genres and even some hard-rock. One could expect them to have three or four big names and then some underground bands but no, they have awesome line-ups.
Second, these are small Fest and can't be compared to Wacken in any way. Not in size, not in budget, not in attendance. However, like i said in the first point, they have great line-ups.
Third, these are the kind of 'big' bands I think everyone is expecting for Wacken. Well, at least I would like to see them all in Wacken with one or two exceptions.
Bottom line, I understand the critics, after all we'll spend great deal of cash to go there and expect no less than a great line-up...