I just went through MacRumors' archives to see exactly how reliable 9to5Mac has been in the past when they claimed they had information from "a source inside Apple". I tried to find every rumor they started between the release of the unibody MacBook Pro and the rumors of this new MacBook Pro:
Apparently, 9to5Mac has been wrong every time they have made predictions about future products, except when their source was
Mr. X.
Mr. X seems to only have access to products names, SKUs and prices a couple of days before their release, indicating he probably has access to a retail/shipping inventory of some sort.
Never in the past has 9to5Mac revealed new information leaked from Apple's HQ (Cupertino) or from the supply chains (Asia). Other than this Mr. X who obviously can't know details about the next MBP or iPhone yet,
9to5Mac has never had a reliable source inside Apple in the past. 9to5Mac hasn't mentioned Mr. X in any of those previous "leaks".
Based on their past "leaks from inside sources at Apple" (not by Mr. X), it's safe to assume the 9to5Mac articles are 100% BS written only to generate traffic on their blog and gain profits from ads. Not that anything that they said is impossible, but it's probably just a compilation of guesses they made.
I suggest waiting until WWDC before making judgements based on 9to5Mac's claims which have not been confirmed by Bloomberg or Joanna Stern.
Those include: Removal of the ethernet port, removal of the FireWire port, 2 Thunderbolt ports, 2 3.5 audio ports (in/out), 3 USB 3.0 ports, battery meter and power button on the keyboard.