I have the earlier blue bound cover book (just called "Garbage Collection"). The book you are referring to is brand new and I haven't looked at it yet, but given that the first authors are the same, it should be good.
I've had and enjoyed both. The latter has less about the fundamentals, but adds chapters on real-time GCs, concurrent GCs, and other advanced material. (Most of whose research probably came out after the first edition.)
If you're interested in GCs, I would suggest getting the newer edition for advanced material, and deferring to freely available papers such as Wilson's "Uniprocessor Garbage Collection Techniques" for fundamentals.
If you're interested in GCs, I would suggest getting the newer edition for advanced material, and deferring to freely available papers such as Wilson's "Uniprocessor Garbage Collection Techniques" for fundamentals.