Guild Wars 2

and when is guesting actually coming? its already 28th but still no update?

No1 knows yet… Wait for the update.
If you are in Europe you may expect the update early 29th:

https://forum-en.gw2archive.eu/forum/game/gw2/Flame-Frost-launch-time/page/3#post1304467

Any idea how much will it cost to transfer into a “very high” population server?

I don’t know if they will put a price based on Tier, on Population or if they will put the same price for every one. Either way, no1 knows for sure the price!

Only thing we can do is wait