I am already using E17+Slim from Debian Testing (vanilla) with Kernel 3.2 on P4 2.4 Ghz with i915. 32bit.
Memory usage is: 80MiB loaded desktop. 150MiB with VLC. PulseAudio is also loaded.
This is VERY functional, VERY nice desktop, sans very few translation bugs, like non-translated categories in main menu with e17 possibly simply picking wrong translation.
Feature level is PAST XFCE or LXDE, its near KDE4, but without Plasma widgets. Also has "new install manager", which autolaunches when first logging in. Very easy to configure, very through-thought.
For comparison, LXDE uses 120MiB, XFCE - 160MiB bare.
... However,.. the whole eyecandy might also get into the eye of somebody "technical",.. so I could imagine he picks these two instead of more "tasty" E.
Yes,.. E is fitting the very definition of "tasty low-carb cake".