A brochure was posted to the Lincoln Property Company's website which includes an updated building elevation showing 67 floors for the proposed tower at 608 Guadalupe. The height is still shown as 847 feet.
The website also includes some updated renderings with a few design changes. Besides gaining 5 floors and a few facade tweaks, it appears there's a "hole" at the top on the main roof with a balcony and what looks to be a public space on what is the 67th floor.
http://www.lpcaustin.com/properties/600-guadalupe/
View from southwest
View from southwest
View from southeast
View from south
View from northwest
View from northeast
View from west
View from north/northeast