The total blogosphere has been doubling in size every five months or so for the past couple of years. That’s 80,000 new blogs set up everyday. IceRocket’s Mark Cuban questions in his blog, though, about how many of these blogs are legit and how to index them.

“Unfortunately its impossible to count the number of blogs in the blogosphere due to the number of spamblogs, splogs, zombies, whatever you want to call them,” writes Cuban.

Cuban settles on the lingo, eventually choosing “splog” as the new Internet word of the day. Personally, I’d have gone with “blam,” but who am I?

After Technorati’s Dave Sifry reported in March that nearly half of all blogs in the blogosphere are stagnant (not updated for six months or more), the proliferation of splogs (blams) is a reasonable surety due to free and easy setups.

This presents quite a challenge for blog search engines as well as they will have to scramble to develop algorithms especially efficient at filtering out bogus content.

Of course, bringing up the issue gives Cuban a chance to slam Google’s hosting service Blogger.com while praising IceRocket’s splog filtering capabilities.

“Blogger is by far the worst offender. Google seems to be working hard to adjust their relevancy indexes to exclude splog from having influence on search rankings, but they don’t seem to be doing anything more than removing reported splogs,” said Cuban.

But he does make a valid point that it will become increasingly difficult for search algorithms to differentiate between legitimate blogs and splogs, which is bad news for the innocents who may be overlooked while being indexed.

Cuban suggests using an email system to verify when legitimate posts have been added similar to those used for comment spam (which Salsa Dave and I shall call “scam.” Dibs!).