Seven years after Machina / The Machines of God, the Smashing Pumpkins reformed and released Zeitgeist, it's pretty clear to me that Mr Corgan works better under the Smashing Pumpkins brand.
This album is not as heavy as Machina, you can really find a lot of correlations to their past albums throughout Zeitgeist, but you can't really compare it to another album as a whole, it is a different sound, even if it is every blurred together.
Come on, Let's Go, and Bring the Light, which starts off like 1979 are the two best tracks on the first listen, almost so that they do tend to stand out too much compared to the rest of the album, Doomsday Clock opens the album well while Pomp and Circumstances closes the album in a Mellon Collie kind of way. Apart from the ten minute 'United States', which I don't know what to think of, some parts sound great, other parts are terrible and should of been left out in my opinion, the rest is certainly good, but I don't think the album flows very well, the first half definitely doesn't work as well as the last four tracks.
Overall I'd give this album 4 out of 5. It's no Mellon Collie and the Infinite Sadness, but it's certainly up there with their other albums and should be on the listen list of Pumpkin's fans.