From a brief review of some major godblogs, I doubt that Robertson's endorsement of Giuliani will much of an impact in the evangelical blogosphere.

Evangelical Outpost is busy in a discussion of why waterboarding isn't Christian--which Scriptorium endorses; the commenters on Between two Worlds seem completely nonplussed by the endorsement.

"I am dumbfounded"
"God forbid the rest of us with a decent sense of conviction (by the grace of God) jump on that bandwagon."
"I am just ... well it's just ... wow. Maybe it is the end of the world?"
"My point here isn't that Giuliani is good, but rather that Pat Robertson is irrelevant as a spokeman for Christians."

These two responses seem fairly standard:

Pat Robertson is endorsing Rudy Giuliani for President despite Giuliani's pro-torture and pro-abortion stances.

(from Alaska Report, written by an old Robertson campaign volunteer.)
Daimnation

Robertson endorses Rudy

This bombshell makes me think much more highly of...McCain, Thompson, Romney and pretty much everyone else running for the GOP presidential nomination. (Yes, even Paul.)

(from Daimnation!, which I think is a Christian blog).

In general I do not like to write about endorsements. It is something like writing about polls, except slightly more condescending. This may have something to do with being a Vermonter; endorsements almost make you not want to support a candidate, as it suggests that you'd be doing it for reasons other than your own good judgment. But I also suspect that people who are not second guessing what other people are second guessing (as in Hotair.com, who writes, "I’ve written of my ambivalence about Giuliani, but the prospect of religious conservatives handing the Democrats victory next year by sabotaging the GOP nominee ought not be on the table.") are not nearly as susceptible to the seductions of "chuck norris! oprah winfrey! pat robertson!" as some reports might suggest.

In short, I think the godbloggers are probably representative; this means less than you think.