I think that the purpose of the lawsuit is precisely to cause this effect, I'm no worried about this, also, there are many forum owners running XenForo so, in the worst scenario that IB ruins XenForo something like XenForo 2.0 will arrise. My advice is: purchase XenForo, don't be afraid
Don't cause the effect IB wants! XenForo is our hero!
If you are worried then why not simply wait until it's resolved? In the meantime, the software will continue to improve and hopefully go "gold", so when this has all blown over you'll have not only a better XenForo to download but a bigger community of help/mods here to utilise.