Look guys I love Fluxbox and I love LMDE, but I have been enjoying that combination ever since LMDE was first released, you don't have to wait for anything. I take it you do know that Fluxbox is just a window manager, it can be added to any distro you like, including LMDE. If you have an existing Fluxbox install then once you have installed it onto LMDE it is a really good idea to copy ~/.fluxbox and ~/.mint-fm2 from your existing distro into the new Fluxbox version, but even that is not essential, the beauty of Fluxbox is that it is so easy to configure for yourself even from a base install, the only skill you need is to be able to type, because all its config files are plain text, not hideous xml. Once you have adopted one of those strategies you will have a perfectly good Fluxbox LMDE. Now I know it won't be as good as what Kendall will produce, but it is a damn good alternative while you are waiting for him to finish his latest version.
Apologies if I am stating the obvious, but I am not clear from reading this thread if people are aware that they don't have to wait for the best distro/wm combo in the Linux world - it is available right now - DIY
Fujitsu Lifebook AH532. Intel i5 processor, 6Gb ram, Intel HD3000 graphics, Intel Audio/wifi. Realtek RTL8111/8168B Ethernet.Lubuntu 13.10,Ubuntu12.10 (Unity), Mint16 (Cinnamon), Manjaro (Xfce).