We've heard plenty about Project Dark lately, including new unlimited plans, 21Mbps HSPA, and new handsets. The newest rumors, courtesy of Boy Genius Report, are whispers of Rent-A-Center style, contract-free unsubsidized phone purchasing and tiered unlimited plans. Updated.
Obviously T-mobile is attempting to expand their customer base through Project Dark, and part of the approach is to entice customers who would normally be forced to prepay monthly dues as well as full retail for a device:
"Even More Plus" will give those who would otherwise qualify for FlexPay the option to finance a phone. [...] Our sources tell us that the phones will not be subsidized and so there won't be contracts for the devices, which means you pay the full retail price over the course of a set amount of time (up to 20 months is what we're told). Not bad - for a $500 device over that time is just $25/month, as an example.
The next step is offering the "Most Affordable Unlimited Rate Plans" in three flavors:
[U]nlimited voice, unlimited voice and text, and unlimited voice/text/data all priced at $40, $50 and $60, respectively.
All unconfirmed rumors, of course, but moves like this could definitely help T-mobile leap up from fourth place in the Great Battle of the Carriers.
Update: The folks at Boy Genius now have some screenshots showing the tiered unlimited plan and the FlexPay options.