Well, Melissa Bianco (5-year veteran Level Designer on the CoH team) wanted to change it... and change it she did. In fact, there are so many changes it's impossible to list them all here. You really need to go check Melissa's new dev diary to get the full rundown. Needless to say, veteran players will love the new and improved Hollows. It's been simplified, streamlined and now reflects the style of Striga, Faultline and other zones in that it's more of a hybrid zone (part city spawns, part hazard).