Yes, but any hacks you've done will crumble into ruins, and your skin won't work. There is a page in the wiki manual that talks about upgrading your skin from 0.9.2 to 1.8, but (as far as I know) no documentation covering changes from 0.9.0.10 to 0.9.2 so you might have a bit more of a struggle than what that page covers.

You might want to upgrade first to 0.9.2 so you can get your skin happy, then after you're all settled in to your new version move on up to 1.8.

Bottom line though is yes - you can upgrade directly to 1.8.

Thanks, I think I've decided that 0.9.2 is the right version for me right now anyway... :)

Now, for my next question...

is there a "tricky stuff" page ( http://manual.b2evolution.net/Tricky_stuff ) in the wiki somewhere that refers to 0.9.2 instead of 0.8.9?