The features of the current version may or may not be included in the final built.The features of this current version include offline reading modes, immersive and night modes, site-by-site settings for privacy and security and the ability to save downloads in a preferred location and name files before saving them. Cyanogen Mod have also made it clear that Gello wont be available to the devices with small partitions. And yes, Gello will be available to all Cyanogen OS very soon as soon as the final built is out.
Personally I feel Gello would be one of its kind, since Cyanogen is having hands on everything android comes up with and since they make it far better versions from Google I guess its going to be just like those OSs, being awesome. I expect Gello to be out with the nightly updates or something.