I've stayed mostly dark on H5 news. I've looked at nothing of Hunt the Truth, but I do hear it's good, ILB good.

As far as where to jump back in, you might want to seek the comics, they are filling in the gap and leading up to whatever story is in place for Halo 5.

You don't really need to finish the K5 trilogy. The last book is better than the first two, by far, if you're feeling lucky, but a simple trip to Halopedia for a summary should suffice.

I personally really, really liked Broken Circle but it likely has no major impact or connection to H5, I'm guessing.

I would say watch with caution. A lot of what they've done so far is just fan service. Yeah, Buck is back. Big whoop.

Show me how you're going to redeem yourself, 343. Show me.

That's about were I am at this point. Watching, waiting.