Ah Wow!!!
I didn't think of touring the whole CoD yesterday. For the Christmas Tree in our Relto, I'm a bit puzzled

...I didn't see it yesterday and it should be very visible
Maybe it's an on-going thing.
@janaba: I'll be part of TOC party that's for sure. The CoD is really the best place for such event. I know each shard will have their own twist but TOC has more freedom than let say "Cyan's MOULa" event organizers.
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EDIT: I found a great total of 10 gifts spread all over CoD
The 7 that Wamduskasapa pictured (including the one I also found in the Ferry)...
And 3 more...

One big gift located near the Party Dance Floor

2 small gifts located in the bar section
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I also found

the obvious tree in my Relto (I don't know what I was "up to" yesterday no seeing it...)
Mine has a specificity though...it has a cat tail
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And finally, I don't know if it's a coincidence or it was already there but I found 2 objects with christmassy colours:

Inside CoD's museum

Inside CoD's pub, a rubik cube
...and BTW, there's a room on the side of this table, if you enter it, you'll see a button, touching it you'll trigger a panel. The panel closes the room.