They seem to plan to explore Alpha 2 in a future article, so I assume the current Beta 1 too at some even later time; but what I don’t get is: what’s the point in writing about those earlier versions? I don’t see any, and I didn’t find any explanation anywhere near the beginning of the article
They started with BeOS R3 and progressed chronologically through its various successors before just recently reaching Haiku. If you’re into OS development, I highly recommend giving the entire series a read.
Maybe to discuss the progress in later articles