It's about 70% true, 20% outdated, 10% mistranslated. And 100% butthurt vs rochand forum over Lindvior for some reason. Either way Terragamers is an organized assortment of google-translated information of Lineage 2 GOD updates and Rochand is a discussion forum about different aspects of L2 both current and upcomming. Rochand is pretty spot on with their information, however information there is rather hard to gather since its not organized due to being a discussion site and not a l2wiki-like site; your best hope is using the search function there and doing lots of reading or just being frequent on the forum (posts don't come by too often until something important is found or a new update is coming). Don't expect any site with both 100% accurate information and organized for easy viewing, either one or the other or neither. :)
TL;DR
Terragamers for mostly accurate, organized upcoming update information.
Rochand for intelligent general L2 discussion and scattered, accurate information.
Please don't lump the two sites into the same category as most people here do as they serve different purposes.