When I was looking for my summer stay a few weeks ago, I could book them - there were no standard RIV for my entire week, just tower and preferred. Standard (dislike the view but I understand it is good looking out from higher floors) is a passable value, the preferred is very expensive. The tower studios do not seem as popular as we thought they would be (given how few there are) as I think with those when it comes down to it, it is an extremely underwhelming space compared to what is available elsewhere. You may get a lot of 11 month bookings with the intention of switching out. In August now, they are available for 16 of the 31 days! Compare to standard which have only 8 days- and hardly any concurrent- the towers have a whole week at the end of August (in fact longer- 24 August to 1 September every day so you could book a 9 night stay). I also think when people stay in these (new owners will understandably want to stay in home resort) then realise what you get for more points than say a Boardwalk studio, many could decide its one and done in them and go for standard next time or go to another resort.
I will be interested to see how it pans out though because with the high points requirement for rooms there, they could be popular with other owners just wanting to try Riviera and with so few of them it may pick up.