Have just listened to the MTT M9 and Rattle M8.
First, the Rattle is very good but cannot supplant the Solti M8 (Decca Legends - remastered 96kHz 24-bit). I don't know what it is about the Rattle, but from the opening bars, it is really apparent that the singing is not as good as on the Solti. If the singing isn't really top notch in this symphony, I don't know how anyone can claim that it is so super-super-top-top-top the way gramophon is doing. It's really very good, but not on the same plane as the Solti.
The MTT is another thing entirely. It is excellent. Really superb sound and superb musicianship. However, it does tend to move a bit more slowly in places than I prefer, so I have to rank it as a co-favorite with the Ancerl and Chailly. The Ancerl may just edge it out for artistic impression for me even if the sound quality is not quite as good. It definitely is reference quality though, and when played in SACD extremely intense. (I have to make room for another M9 on the ipod now! Or a good excuse to upgrade to the photo 60gig.
As for other favorites,
M1: Kubelik, Bernstein DG
M2: undecided, but I have Bernstein (sony), Litton, Blomstedt (maybe cause of the affinity with the themes in the Maestoso) in heavy rotation. The Litton, SACD/hybrid is definitely the top for sound.
M3: Chailly (really has me humming Brahms every time I listen to this!)
M4: undecided, James Levine (new to me!), George Szell, Yoel Levi are all up there.
M5: Kubelik, Bernstein DG,
M6: Bernstein Sony, but I'm not completely happy here with any of the ones I have, including Kubelik and Yoel Levi. This symphony cries for SACD or dvd-a format.
M7: Bernstein Sony, Kubelik DG and MTT/SFSO when it's released. I heard this in concert and MTT really owns this symphony.
M8: Sir Georg Solti, Kubelik Audite -- wonderful singing there!
M9: Karl Ancerl, MTT, Chailly (SACD)