Slackware and 2.6
 

When is a version of Slackware with the 2.6 kernel expected to be out?

Just upgrade module-init-tools and grab linux-2.6.6 from:
http://www.kernel.org/

Then you'll have slack with a 2.6 kernel

It's out now. Go to www.kernel.org download the 2.6 kernel, compile it and run it.

Really... ;) You don't need a newer mod-init as it stands now with 9.1... It's all set up for 2.6 already.... The version after this coming one will have 2.6

Just to answer your question as you asked: No one knows... The best way is to upgrade by yourself (but I guess you're having problems with it...)

As soon as Patrick deems it darn good 'n ready. :-D

Slack 9.1 is indeed 2.6 ready, though. As stated before, just compile and run. I've seen some unofficial packages laying around for 2.6 on slack as well.

--Shade

I got a lot out of compiling my own 2.6.6 into slackware. Now I've got a kernel matched to my machine without a bunch of extra stuff and was able to add stuff I needed. If you want to learn linux and how it works, you owe it to yourself to compile your own kernel.
There are lots of good guides on how to do it on this site. Just make sure you understand what your hardware requires.