According to the FAQ Yrgmal Genestealers are Special Characters as well, it looks like a simple mis-use of the term Special Character and a misunderstanding on maddermax's part.
It's confusing but again there is no Foo rule in 40K, Characters are defined as Independent Characters and Upgrade Characters. Special Characters are not Characters. Thus the Swarmlord et all are not Characters so cannot be Deathleapt or scared by Dante. Very much like Psycho-Tycho and Mephiston.
Aramoro
Just going by the FAQ.
"Tyranid special Characters. Are Tyranid Special Characters considered to be special versions of the standard creatures of their type for the purposes of using psychic powers, biomorphs and special rules?"
A character? I don't know, but it's GWs fault one way or the other :wacko: They say Swarm Lord et al are characters, Deathleapers rule says it affects characters... And this just goes back to "GW are bad at writing rules".
Now, back to the BRB, "Armies normally include two types of characters", not that ICs and upgrades are the only types of characters there are, leaving open the possibility that there can be other types of charcters. Depending on how you do call it, remember that this will also affect, DC tycho, Mephiston, marbo and more than a few others around the place. Most of them are fearless however, so the list it actually matters for is usually all the ones with Psychic Powers: swarmlord, mephiston, Inquisitor Lord Karamazov.