3g or 2g, you will probably be ok TO GO TO OS 3.1

Apple is pushing v3.1 now. I strongly recommend you do not upgrade.

If you have a 3gs, if you update now, you may never be able to jailbreak ever again.

If for some reason you think you must upgrade,

at the very least make sure that you get your ecid shsh done via the home page of cydia first by clicking the heart.

If you didnt do this or dont understand, do not upgrade!

If you have a 3g or 2g, you will probably be ok ,

but you should still wait a few days to see what happens with the jailbreak. 3.0 is plenty stable and there’s no rush to upgrade to 3.1.

Also, whatever bug you think you have that it will fix it probably will not fix as is always the case.

As always, will keep updates here and a tutorial posted when jailbreak is released.