It depends how your WP comments template retrieves and displays the comment count.  The most common is by using the WP template tag comments_number().

If this is the case then this can be replaced by:

spCommentsNumber("0 Comments", "1 Comment", "% Comments", true);

which has the same format but wll add the topic posts and blog comments together.

Thanks for the reply. So you’re saying I should modify the template directly? Or would I be able to put this in the user function.php file? I ask because I use the PageLines framework and I am reluctant to futz directly with the code, and I don’t see how I can use the function you’ve suggested without doing that.

you would want to modify the wp theme comments template file…  typically comments.php but themes can do it many ways…

or if the theme is well written and provides some hooks to be able to get at it without modifying the actual files, that would work… many of the better themes have a bunch of hooks these days…

On the PageLines (the framework I’m using) site, one of the developers tells me:

We use http://codex.wordpress.org/Template_Tags/get_comments_number
In comments.php
printf( _n( ‘One Response to %2$s’, ‘%1$s Responses to %2$s’, get_comments_number(), ‘pagelines’ ),

I’m willing to modify comments.php, if necessary, but I want to make sure there’s not a way to change this that doesn’t mean my modification will be wiped out the next time the template is updated.

That is currently the only way we do it.
There is a planned task for some updates to blog linking and I am pretty sure we will be able to then offer a better alternative as WP have added some new filters that I think we can use. I have no date or version for that particular update as yet as that is still to be decided.