Given the way various leading righty blogs jumped in with both feet to try to discredit the Killian-TANG memos, and (more recently) the GOP talking-points Schiavo memo, it's interesting to note a remarkable degree of reticence from righty bloggers right now (and righty media in general), with respect to DSM.
Especially noticeable in their deafening silence (so far) are Instapundit and Power Line. By comparison, note that for the first couple of weeks after the Schiavo story appeared, Power Line wrote about it more than once a day, on average. (I analyze this in detail here.)
Frankly, I find this silence to be a very encouraging sign. I think these folks realize the memo is powerful, and they have no good defense. They have been hoping it would just fade away, and for the first few weeks that seemed to be happening. At this point, though, a google on "downing street memo" returns 496,000 results. This is one indication of how the story is picking up steam. I think the silence of leading righty bloggers will become more and more embarrasing and impossible to sustain.
Of course there has been a small amount of righty coverage. It strikes me as contorted and desperate. What follows is my attempt at a fairly complete list of this coverage:
http://www.nationalreview.com/robbins/robbins200506060801.asp
http://wizbangblog.com/archives/cat_downing_street_memo.php
http://michellemalkin.com/archives/002656.htm
Helpful rebuttals can be found here.