Fan server Nostalrius got shut down a few days ago following a cease and desist notice issued by Blizzard to the team behind the clandestine operation, to the chagrin of hundreds of thousands of fans who staged a sort of symbolic protest by populating the server, standing around and casting spells and "shouting" various slogans through chat. According to the Nostalrius team, some 800,000 people were registered on the server and of them about 150,000 were active players. It is however unclear how these numbers were tracked.
Nostalrius' popularity was owed to several factors, probably the biggest one of which was the fact that one didn't have to be a paying WOW subscriber to play there, although many of their players were indeed just that. The other factor was the nostalgia one: Nostalrius ran version 1.12 of the game, which dates from before the Burning Crusade expansion and as such, it is a purer, more "classic" form of WOW. According to some of Nostalrius' volunteer administrators, who answered questions on Reddit, the aim of the server was to provide a version of the game which Blizzard no longer featured. They also urged Blizzard to open up legacy servers and they declared their willingness to help them do so by offering up the data, knowledge and experience they have accumulated over the years through Nostalrius. To this end, a petition has apparently been launched, which has thus far gathered more than 85k signatures.
According to some though, Blizzard will probably not wade into legacy servers, for several reasons, one of which may well be the lack of the original code. They're also looking to start offering old content within the current game, through the Timewalking feature. There's also an obvious lack of political will on Blizzards part which is probably the biggest hurdle to this undertaking.
Philip Thalberg has been working for the eSports news section of Gosugamers since 2004.