Regularly means at least once per day, or per appropriate log in period for when you are interacting with the game or community.
For the server merge question:
TNRH is one of many merged realms, and one of the few RP-PvP server clusters. The other servers are Emerald Dream, and the merged realm of Lightninghoof/Venture Company/Maelstrom (LVM).
Put together, per Warcraft Realms data, Emerald Dream makes up 2/3 of the RP-PvP server populations. EG, if added together, RH, TN, and LVM are 50% of ED's population.