Cut/paste format didn't work...
 

In 5.0.1 beta 4, I just selected a couple words of text, did a format copy, went to another canvas, selected some text and did a format paste. Nothing happened. Odd, I did the same operation yesterday a bunch of times and it worked fine.

If I just selected the text in the target and changed color via the inspector, that worked okay.

Further diagnostics... everything is okay if I am cutting and pasting a color format change from and to Verdana, Regular 10 either on the same or different canvases. BUT, it won't work on Gills Sans, bold, 12 copying and pasting maroon onto black. Again, if I change the color in the inspector, no problem. But format copy/paste won't work in this case.

Followup trouble
 

Okay, the font doesn't seem to be the issue. I just tried pasting an object style (text color) into some text in a text area with the font and color that worked before and still the paste didn't work with and the entire text area became selected (left text insertion/selection mode). What?

I whittled down my file to a single example for you to try out and see if you can reproduce. In the attached file try selecting one of the words colored in maroon, Copy Object Style, then select a blue word in the other text area and Paste Object Style. For me, it doesn't work.

(and I did try killing and restarting Graffle with no change in behavior)

Okay, I just discovered Font->Copy Style. That does the job for me, however, now I need two pairs of keyboard shortcuts for Copy/Paste Style vs. Copy/Paste Object Style. And I could SWEAR that I was copy/pasting font styles with beta 3 using just Copy/Paste Object Style. Maybe that changed? Weird. In any case, I request the feature of merging both pairs of commands. Otherwise, I've got to remember cmd-C, ctrl-cmd-C and cmd-opt-C - doable, but unpleasant.

Copy object style is for the entire object, the commands I think you're looking for are in Format --> Font --> Copy/Paste Style.

Hope that helps,

Looks like we posted the same answer simultaneously! Please see my feature request though.

Final thought / realization
 

Sorry, didn't mean to start a blog here, but I now see the wisdom of having three separate copy/paste commands. You get three buffers, which can be nice if you keep the shortcut commands simple. I can hop around quickly with ctrl-cmd and opt-cmd variations on C and V making alternating style changes without having to refill the buffers.

I humbly withdraw my feature request.

You can of course, use the Keyboard Shortcuts tab in the Keyboard & Mouse preference pane in System Preferences to create shortcuts for these menu items to your preference, if I recall correctly we did change from v4 to v5 to better match what all the other applications on OS X were using.