Not any adds either in magazines or out on town here in Stockholm/ Sweden, at least I have not seen em compared to other brands.
But there have been quite a few phoneshops i've been asked to show them the phone (pre-release N900 and later on retail version)

So I guess the N900 must be the most "secret" phone ever by Nokia.
Still not seen any device In a phoneshop and they still repeat the same old "it will be in stock soon"

Guess that will be Meego devices with the current delivery speed over here.