I *love* the idea of Second Run and Arrow coming together and pooling their resources on more than a basic distribution level, featuring more releases like this one or Ikarie or other things that have been restored being upgraded to BD with some more comprehensive features, though I guess it could have a negative impact on Second Run's catalog's sales if it became anything resembling a frequent partnership.
Second Run have been branching out to Blu-ray, and Arrow now handle all their distribution. I've also seen Arrow Academy on social media posting about Second Run releases, so the two do seem very cosy.
What might be happening is Second Run and Arrow Academy collaborating only on upgrades to Second Run DVD titles, since Second Run have sounded hesitant to that idea - they will obviously cost more to produce, and arguably have limited appeal considering many Second Run DVD collectors will be hesitant to upgrade. The benefits of this would be more exposure to Second Run's catalogue for Arrow collectors, and Arrow's higher budgets would presumably mean more new on-disc extras could be produced. I dunno if Second Run's sales would take much of a beating from the odd upgrade, since they primarily target DVD collectors and if this is a collaboration, Second Run would still receive some revenue.
If this does turn out to be the case and not just some speculative dream scenario, I agree with your suggestion that Ikarie XB-1 wouldn't be far behind. I very nearly bought the DVD in one of the recent Arrow sales and regret not getting it now - obviously that sentiment would disappear after an announcement of a Blu-ray edition!