I had more than 100 items to review and still was I seeing words in writing practice that said "new word" (I still had almost 200 items to review then). The queue didn't behave like that before I think.
I though that the reason was that it were words that were added in definition practice yesterday and that they are automatically added in writing practice queue as well, is that so?
But now with still more than 100 items left to review skritter keeps on adding new words, hence my review queue goes down very slowly and I dread the time to come, with so many new words at the same time I am going to have a review of even more tomorrow or later today.