According to the description...
The new weapon lets you lay down 16 stickies, if you're looking at stickies when you detonate them, only those on your screen explode. I'll infer that if you're not looking at any of your stickies, then they all explode. Also, you can use them to explode other demo's stickies.
So let's take an example from Blackmesa. Let's say you're in the Iron Horse spot, guarding the blast doors. Now you can lay down 8 stickies over the grating, 4 over the entrance from the vents, and 4 more at the third floor vent entrance. If you watch the various spots, you can detonate each group separately. If someone comes from blast doors: KABEWM! If someone tries to sneak around from the crab room: KABEWM! And if someone gets past your other two traps: KABEWM!
This is a full-on upgrade to the sticky launcher. Now to remove a fully entrenched paranoid demo, you'll need an uber or another demo with this weapon to destroy the stickies.
The only downside is they have a longer priming rate, so if you're using them like rockets or someone gets in close past your defenses, then you'll probably die.