KivArn wrote:
sensor towers can be used as objectives (As could the drone sentry guns) - these didn't really make the list for the same reason that tarrantula sentry guns and radar towers aren't there for the imperium... they wouldn't add anything particularly to the list expect possibly special rules.
Their fine for scenario play, and possibly if there was a seige variant Tau list (though i seriously doubt the tau would ever get into one of those... they don't have the manpower to effectively fight a war of attrition) but for the standard "codex" list not really the place for them

As to the great knarlocs....i have no idea - i don't use kroot anyways so i didn't even notice xD
Hope this helps

They were a part of the standard list as written by GW, I guess I'm not seeing why they don't have a place now. They perfectly fit an epic tau army. You wouldn't be forced to take them, but I think they should be an option.
You wouldn't need any special rules for them, as they didn't have any in IA3. Additionally; the tetra is included in the current list, and that's an IA3 vehicle, so there's president to include the others as well.