The short answer is yes.
For a longer answer, when LMDE was first introduced (and it was still pointed directly at the Debian testing repos instead of using the Update Packs), testing was frozen in preparation for the squeeze release. The first two ISOs (201009 and 201012/201101) were released during this freeze. During this time, LMDE only received the updates that Debian was pushing through to testing. I would expect that when testing freezes again in preparation for the wheezy release (June of this year if memory serves), LMDE will again only receive those updates that get pushed to Debian testing, albeit this time through the UP infrastructure.
AMD Athlon II X4 630, 4 GB DDR3 RAM, Nvidia GeForce GT 430 - 64-bit LMDE (Gnome3) tracking testing, 64-bit Archlinux, 32-bit Windows XP
Aluminum Unibody MacBook - MacOS X 10.7 "Lion"