Sorry for troubling you again, KING!
Let's say it's 4x multi threaded, so you should be able to make it more (and I believe you could), provided, you may add a box for user to input how many threaded he/she wants.
Oh yeah! .. probably you could add some kind of timer (timeout) so, when it waits more than the timer it will skip and mark it as failed, then continue to next blog. And again the user may input how much time it wait for.
And lastly, is there any though, of expanding your program to be able to work on other comment platform, i.e movable type, blog engine, etc...
if you could add all above, perhaps you could start selling something, ... but keep the free for me... lol!