Short answer: Load times, that's why i buy the bank slots.

My friend and I are also having this issue. I suspect it is based on hitting 50. Currently the only way to track if I got a lore object etc is to watch for legacy experience.

If by "bugged" you mean incredibly hard to find, rare and requiring cooperation with others, yes they're bugged. Otherwise, no, they exist and are probably working as intended. If you want to find them slightly more easily, shut off grass completely so they don't obscure the cubes.

The 6th "datacron" is the cave near the dark temple where matrix shards are combined into matrix cubes, run into the cave until the lore pops.

My guildie and I have gathered every datacron in the game on Empire side (Except the corellia presence one for me since I made the mistake of choosing body type 3, and cannot fit through the gap) and are at 66/67. We counted the number of datacrons we obtained and it did in fact come to 67. The problem is that one of the Ilum datacrons (not sure which) is not counting yet. According to one of the datacron posts here, it may be the +Aim one that is not working. So, all are available, but shockingly i know, there are a few glitches.

Given that Bioware has chosen to avoid looking for group mechanics across server and stressed building of a community as well, I HOPE we can get a server forum up. I already have a loot ninja to report on it darn it.

However, my favorite move is to cloak mid-combat, blackout dash, mind trap an incoming patrol, run back to the mob and pick it back up, takes like 6 seconds and scares the hell out of the healer, who is USUALLY still alive. I had one mishap thanks to the UI bug that prevented me from clicking/hotkey using any ability. But, overall, it is great for preventing a potential wipe due to an incoming patrol. Just make sure it doesn't have boss immunity.