On the passing of Andrew Brietbart

This morning I woke up to discover that conservative blogger Andrew Breitbart had died suddenly at the age of 43.  The media commentary on him and his untimely demise consisted of much praise and eulogy, some circumspection from political opponents--and a fair amount of pissing on his grave.  Most of the glee at his death came from sources that aren't worth commenting on, but one interesting remark came from Matt Yglesias:

Conventions around dead people are ridiculous. The world outlook is slightly improved with @AndrewBrietbart dead

The discussion of this subject is interesting where Breitbart is concerned, as he himself famously and publicly danced on the tomb of Sen. Teddy Kennedy when the latter passed away from cancer in 2009.  Breitbart justified this on the grounds that Kennedy was a particularly noxious bad actor in US politics, deserving of special scorn. 

But given the observations of both Yglesias and Brietbart, what are--and should be--the social conventions for dealing with the death of a political opponent?

My personal opinion on Breitbart is as follows:  I disliked much of his work.  I thought his temperament was foul and obnoxious (I'm not speaking of his conservative ideology, but of how he disparaged and held in contempt those who disagreed with him), and some of his journalistic practices sleazy and unethical.  I do not know him personally, though many who do have praised him as a nice guy in person (a remark commonly uttered about our political provocateurs).  I'm certainly not happy to hear he's dead--he's only two years older than I am, and it's rather clear from the circumstances that neither he nor his family were prepared and ready for him to die.  Nor am I about to join in the sort of not-glad-hes-dead-but-glad-he's-gone bile that is frequently offered up when a controversial figure dies.  I was somewhat pleased to hear of the demise last year of Osama Bin Laden--not joyous, certainly, but at least relieved; and I did not mourn the passing earlier this year of Kim Jong-Il.  But both of these men were monsters; Breitbart (and other players in US politics and media), whatever his faults, is not in their company.

But what sort of conduct is, or should be acceptable when someone controversial passes--both in the hours immediately after the death, while the family mourns, and long after the dirt hardens over the proverbial coffin?  Is it ever acceptable to express joy at someone's passing, or to damn them to Hell (or the equivalent in other religious or cultural traditions)?  Is "good riddance" and appropriate response?  What of no comment at all, or invokation of the wise words of Thumper the rabbit?  ("If you can't say sumthin' nice...")  Does it make the pain of the surviving family worse to hear public exultations of their loved ones' passing, or does this matter?