Hi Mike 949,
[quote]
The mattresses we tried were the newer models that use the new “ActiveFusion” gel technology to keep things (supposedly) cooler. According to the information available at the store and in some places on the web, ActiveFusion entails infusing gel (what kind of gel is unclear) into some of theTalalay Latex (not all layers), as well as into the yarn that’s used in the ticking fabric (that part sounds a little far fetched, although it is stated in the website referenced below). We found it to be very cool and comfortable. You can read more about the Nutrition model (with ActiveFusion) at the following online site that also sells PLB matresses: www.eco-mattress-store.com/pure-latex-bl...tural-latex-mattress
[/quote]. Sealy for example also adds a phase change material into the top foam layer and the cover of their Optimum mattress.
The gel they use is a phase change material which is one of the 3 main technologies uses to regulate the sleeping temperature of a mattress (There’s more about this at the end of post #4 here). It can be added to either a foam or a fabric and can be an effective piece of the temperature regulation puzzle in a mattress.
Pure Latex Bliss has 3 different model lineups. This includes the “Natural” line (which confusingly uses all blended talalay latex from top to bottom), the “All Natural” line (which uses 100% natural Talalay latex from top to bottom), and the Hybrid 3.0 line (which uses various combinations of slow and fast response “active fusion” Talalay in the top layers over a bonded latex/polyfoam core). When they first came out, the “natural” and “all natural” line used “regular” talalay rather than the new Talalay GL material (which is latex International’s name for the material that PLB calls active fusion). Since the introduction of the Hybrid 3.0 line though (which uses combinations of slow and fast reaaponse Talalay GL) … they have changed the top layer of the natural line so that it now used fast response Talalay GL (active fusion) latex in the top layer of all the models. So the have “all talalay latex” models and also various slow and fast response talalay latex over polyfoam depending on which line you are looking at. If the model name is Pamper, Nature, Nutrition, Beautiful, or Worlds Best Bed, then you are looking at a mattress that is latex from top to bottom.
So to recap …
What latex international used to call Celsion latex is now fast response Talalay GL fast response latex and PLB calls this Active Fusion fast response.
What latex International used to call NuForm has not been changed to add phase change materials in it and is now called Talalay GL slow response latex and PLB calls Active Fusion slow response.
Hope this helps and thanks for all your feedback 
Phoenix