I just got the following from Citi Bike:
We’re writing to let you know about a few changes to Citi Bike membership. Citi Bike annual membership will be $163 effective February 5th. This will allow us to keep up with cost of running an expanded system and continue to provide you with great service...
At the same time we’re also making some improvements to our usage fees. We’ve heard from members since we launched that the usage fee structure is confusing and hard to remember. So we’re making it simple. After the first 45 min of each trip you’ll pay just $2.50 per 15 minutes to keep the bike out for longer.
So, rates are going up, though modestly. Overages go up too, at least for the first half hour.