the JLA/Avengers Series that came out 2003. By Busiek and Perez

is it Cannon? or something else?

It's events were vaguely mentioned in the JLA during a battle with Ultra-Man and his cohorts, as to why they could win in the regular universe. It's never been touched upon in the Marvel U (as far as I know).
Of course, now, with the Infinity Crisis changing things a bit, it may no longer be cannon.

I think it tried to be vaguely canon, but of course it ended with the "erasing of memory" IIRC.

Nah, in one of the JLA issues, awhile after it had happened, some of the JLA mentioned Kronas and what he'd done. I'm trying to remember the name of the TPB that was released, all I do remember is the CSA was in it. That was the time Captain Marvel was turned inside out for a few panels.

I remember seeing something in JLA mentioning they managed to beat Kronos - "with help." A very sly reference to the Avengers.

Well, according to Amazon, the JLA/Avengers TPB will be reprinted in November. Blar.

Yes, Krona's assault and the the Cosmic Egg are cannon in DC (The Egg actually resided in the JLA Watchtower being monitored by the League when last seen. No idea where it is now that the Tower and that version of the League are gone kablooey).

Quoted for truth. It would be cool if they went back and showed us some of those snazzy crossovers from issue #3.

The CSA were killed in that series and then reconstitued in the Syndicate Rules story arc in JLA. They blamed the JLA for what happened. It is also where Power Ring went from being Caucasian to African-American.

Definately not.

I mean, you can light it, but where would you put the gunpowder?

But where would you put the gunpowder?

For me is absolute canon!

I love it.

Official yes, just vaguelly canon in JLA.