Does the Orthodox Western Rite represent some form of "Orthodox Uniatism"?
My answer: Yes and No.
A good friend of mine, a Russian Catholic priest, often says that, even though "Uniate" can be an offensive epithet, it also has a positive aspect. The root of the word is "union" and Eastern Catholics view communion with Rome as a very good thing.
Similarly, Western Rite Orthodoxy can be called a "Uniatism" in this positive sense: we view communion with the Orthodox Churches of the East as a very good thing.
So, in this sense, I don't mind being called a "Uniate." No problem!
However, I do not believe that we fit many of the negative images that often accompany the word "Uniate" as an epithet. (Note that I'm not necessarily accusing Eastern Catholics of these sorts of things either; I'm simply mentioning some of the stereotypes).
The Western Rite Orthodox do not represent a second, rival church set up against Rome or ECUSA. The largest units so far have been whole parishes (or parts of parishes) of Anglicans, Old Catholics, and vagante Orthodox who have joined themselves to canonical Orthodoxy. We have been accepted by Orthodox hierarchs out of pastoral concern, not (hopefully) as a way to spite Rome or steal sheep. The Orthodox Western Rite was never conceived to be a mass movement to put Rome out of business, or to swallow up the Western Church.
As Joe ("JSMelkiteOrthodoxy") noted, the Western Rite in the Orthodox Church would be better compared to the Anglican Use in the RCC. We simply represent a pastoral option for folks seeking to be Orthodox, but cannot seem to find a home in the devotional world of Byzantine Orthodoxy.
. Enjoy!