Product Version = NetBeans IDE 7.2 (Build 201207171143)
Operating System = Windows 7 version 6.1 running on amd64
Java; VM; Vendor = 1.7.0_06
Runtime = Java HotSpot(TM) 64-Bit Server VM 23.2-b0

The flex box properties have been renamed/changed and therefore when you receive code "hints" the correct names do not show up.  I  realize that CSS3 is still in flux but the changing of property names is a major change.

http://www.w3.org/TR/css3-flexbox/#changes

The following major changes were made since the 22 March 2012 Working Draft:
The ‘display’ values for flex containers have been changed from ‘flexbox’ and ‘inline-flexbox’ to ‘flex’ and ‘inline-flex’.
The alignment properties and values have been renamed to align with the new Box Alignment module:
	‘flex-align’ → ‘align-items’
	‘flex-item-align’ → ‘align-self’
	‘flex-line-pack’ → ‘align-content’
	‘flex-pack’ → ‘justify-content’
The ‘flex-order’ property has been renamed to ‘order’, to allow it to be used with other layout models in the future.
The ‘flex’ shorthand has been split into the ‘flex-grow’, ‘flex-shrink’, and ‘flex-basis’ longhands.
Negative free space is now distributed in proportion to flex basis × flex shrink ratio, rather than just the flex shrink ratio.
Flex items are now allowed to shrink by default. (The initial value of ‘flex-shrink’ is ‘1’.)
A new ‘auto’ value for ‘min-width/height’ has been added to set a reasonable default minimum main size for flex items.
The effect of ‘visibility: collapse’ on flex items is now defined.
Inline replaced elements are no longer promoted to flex items; instead certain HTML elements intended to be replaced elements are promoted to flex items. This produces a consistent layout model regardless of whether the replaced content can be loaded.
For pagination, the effect and propagation of page-breaking controls has been tweaked and clarified, and most of the details of fragmentation are now informative, allowing UAs to do better.
The flex layout algorithm has received an editorial overhaul, and many error fixes and clarifications were made.
A lot of terminology has been updated to make it less confusing:
	flexbox → flex container
	flexbox item → flex item
	positive flexibility → flex grow ratio
	negative flexibility → flex shrink ratio
	preferred size → flex basis
	hypothetical main size → flex base size
•	Anything that starts ‘box-’ will be changed to ‘flex-’
•	‘box-flex’ → ‘flex-grow’ and ‘flex-shrink’
•	‘box-orient’ and ‘box-direction’ →‘flex-direction’