When I used Snow Leopard, I had access to a lot of miscellaneous symbols in Character Viewer. Now, in Yosemite, I seem to be missing them. Specifically, I can't find ⌘ and ⌥ (they're in the Favorites section of CV, leftovers from SL, so I could paste them here). Are they gone or am I going blind?

They are in the emoji & symbols library which is reached by pressing Shift+Command+Space or selecting Edit > Emoji & Symbols on the menu bar. The symbol set was extended in 10.10.3 and is even further extended in 10.10.4.

Most of us have already figured out that microsoft's giving us the finger, but now it's official

http://www.neowin.net/news/microsoft-is-the-first-tech-company-to-support-the-middle-finger-emoji

I tried that but, even if I scroll all the way down, I don't see them. What am I missing?

EDIT: I just solved it. I clicked the Action menu in Character Viewer (the gear symbol) and chose Customize List. I was able to add Technical Symbols from there. The symbols that I wanted are included in that list.

For the record, when i selected Edit > Emoji & Symbols, nothing happened.

That's only fair. Most of us have been giving MS the finger for a long time.

At the bottom of the window there is a series of small, somewhat difficult to see, icons for different groups of symbols. In 10.10.3 and 10.10.4, if you click on the >> icon it will take you to some additional group icons. Click on the ⌘ icon to get to the Technical symbols set and the first row of symbols in that set is
⌘ ⎋ ⏎ ⏏ ⌤ ⌥ ⌃ ⌄

I don't have any of those icons, not even >>. As I said, I managed to add Technical Symbols to the list (left side of the window) and I saw other lists that I could add if I wanted. At any rate, the problem is solved.

The row of icons joemikeb refers to is only found in the mini Character Viewer window, invoked by clicking the Character Viewer icon in the top right corner of the full-sized Character Viewer window.

In my Character Viewer (OS X Lion) no such icon exists; the only thing in the top right corner is a Spotlight window. That must be a feature in newer versions of Mac OS X.

Got it! Thanks.