I was also a big fan of iTunes DJ, and disappointed when it looked like it was missing. I have found the functionality is still there, more or less as simple as it always was but in a different form.
Let me say right up front that I never used the "voting" option, so I can't talk about that at all.
But I was able to more or less replicate iTDJ from what's already here. I had already created a SmartPlaylist in a previous version so that I could omit anything from the genres like "Christmas" or "Spoken Word". It's just my music library with a few obvious exclusions.
I started that playlist playing with Shuffle turned on.
I then switched to the miniplayer - which really is a big improvement on the previous miniplayer. Click the second icon from the right to reveal the list of tunes about to be played. It's basically iTunes DJ right there.
Like many of you, I liked to fine-tune that list by deleting songs that from the list that I didn't want to hear at the time. At first I was clicking on the X icon on the left of the song, which was slow and tedious to do more than a couple of times. Turns out you can click/shift-click/command-click songs in the list and hit the delete key - boom, gone. The list updates with a new bunch of songs.
You can change the order of the songs by dragging them around. The "Add to Up Next" contextual menu in the library will insert the song into the play order, just like "Play Next in iTunesDJ."
It's true that you can't choose how many songs to see in the list, but 20 isn't a bad number. Yeah, if you want to get all ***** about NEEDING to see 100 songs, please be my guest. Knock yourself out.
The "Go To.." options under the arrow to the right of the song are a nice addition.
I'm not going to tell anyone that they should shut up and put up - I recognise that it's frustrating that software developers can't leave well enough alone - but it's also worth noting that as long as you aren't married to one of the specific features that got removed, there is a pretty decent and iTunesDJ function in there.