The official definition for the word mobbed is "crowd around (someone) in an unruly and excitable way in order to admire or attack them."
Mobbed means being surrounded by a crowd usually in an excitable and unruly way.
a big crowd
If you mean by mob egg-type things, you can't. Only darkness can cause mobs to spawn.
mobs
Passive mobs need light to spawn, and they only spawn on grass. If the aggressive mobs are spawning, then it must be night and the passive mobs will only spawn near torches, pumpkins, glowstone, etc. However, Notch MAY have fixed this in 1.6, but I'm not sure.
Mobs are enemies, so I suppose that there wouldn't have been.
No, mobs will not spawn in water or ontop of half slabs.
In Minecraft Classic, mobs can't spawn, so they can't exist naturally. If you play the Survival Test, and when mobs spawn there, you can save it and open it in creative mode so then the mobs can stay there. However, in Minecraft Creative Mode, mobs can spawn, but they can't hurt you because you have no healthbar.
no, some mobs can't, such as skeletons, creepers and zombies, but other mobs like spiders or endermen, climb over or just teleport in.
They are called troops.
lynching mobs
Yes, there will be other mobs! These include the Blaze, Magma Cube, and the Mooshroom. Also, other mobs will be added over time.
If you mean the enchantment then it makes the sword do more damage for all mobs. Can be really useful in the end.
If you mean in all mods ever, then potentially thousands. Mods are add-ons to Minecraft created by users, and new ones are made every day. To count how many modded mobs there are in Minecraft would be near impossible