So my guild took out Grandfather and The First today in the hopes of achieving server firsts, however, the game offers no way of knowing if that was achieved or not. Most games have a server announcement or an achievement for getting server first, but this one has neither. Even without those things we still thought we had server first because world bosses traditionally take at least a couple of days to respawn. However, a mere two hours later I returned only to find that grandfather was alive and kicking, leaving us with no idea if we were server first or not.
It's possible his respawn was a bug, and if so, consider this a bug report. However, I still feel SWTOR would be benefited by both a server-wide announcement and an achievement for killing the world boss first.
I know all of this sounds very negative (and I suppose it is) but let me add here that this is a minor flaw in a great game that I have been enjoying greatly thus far, and expect to enjoy greatly far into the future.
This was done as soon as the boss was up and there was 8 people to kill it, unless you did it on the first or second day of EGA or a fresh server then your very likely not first. The world bosses spawn again after 90 minutes or so and every time a fresh instance opens up the world boss is up on there too.
It is also not much of an accomplishment truth be told to kill a world boss because its basically a heroic quest for 8+ people of the beasts level. Your placing a level of importance and difficulty on them that is undeserved.
Most people would get annoyed if they kept getting server announcments about kills on world bosses too. Why would anyone want to see spam messages saying "Randomguild6 has killed DerpyWorldBoss4" all day long? Most people don't care about what your doing, and the ones that do know where to find you.