From the announcement:
rade format editions of both TBH and TBP are now available for $11.99 each.
By buying this 6x9'', black and white version of the rules you save $14 compared to the full color books. The trade size is handy and lets me shave a few pennies off the printing costs.
Other books in this size (including reprints of the wargaming books) are forthcoming.
In any case, the old larger sized books will NOT go out of print so you just buy what you prefer.
For those who prefer buying from Createspace, I'll be uploading the same books there too.
These books are dubbed "essential" although the text is exactly the same as the full color versions. The books have been reformatted for the trade size, with different illustrations, so you are not buying shrunk down 8,5x11 books. You can watch previews and read the first 8 pages of each book by following the links.