Welcome to the forums, MrVally!
Golem attrition was removed as it just created extra micro, encouraging players to simply power-down a golem to avoid attrition whenever it wasn't in use.
Golems have been buffed significantly since the 2012 guide, especially the Regen Golem, which now has vampyrism and reduced running costs (I think). Orbital Mass Drivers have also been massively buffed, which makes using golems against core worlds and homeworlds far more risky, unless you take out the OMDs first.
The Golemite AI type does indeed get Botnet Golems, but they only have 10% of their regular hitpoints, whereas I think the others have 50%.
[MINOR SPOILER]
Hive Golems are awesome, but if you're ever planning to attack a homeworld with one... Maybe save the game first ;-)