Dark Reign is gone from the title.
The start screen features, you guessed it, Deadpool.
Dark Reign Story sections now feature a "Dark Reign" logo on the selection for that screen.
The points on my nodes seem to be consistent with what I had prior to the update, so that's good.
Ok. So... Team-up tiles will completely change the way the game is played.
Before the match, you get to select a team-up(s) that you can use during the match.
They go in the same place as bonuses, so you can select either a team-up or a bonus if you so choose.
Still 3 slots, and you can choose either for any of the slots.
To show you how they work, they let you try Fury's Avengers Assemble. I had enough of each color to run all of the heroes.
That move is

ing awesome. Moving on...
After that initial match, the team-ups available to me are BP's Rage of the Panther (black), Moonstone's Control Shift (black), and Wolvie's Adamantium Slash (red). There are two that are unavailable, because the characters are on the team I am using... CStorm's Wind Storm (blue) and OBW's Aggresive Recon (purple). Each character has a set level for that move as well, so the damage is set. Those are awesome moves... moves that you'll be able use even without those people on your team, if you choose. It looks like you only get to use them for 5 matches before something happens... probably have to unlock them again with HP. There's also a 5/20 in the corner, so I'm assuming you can have up to 20 team-up moves.
There was also a note saying that if you defeat people that match tiles, you can unlock their team-up moves.
In the match I played, there seemed to be less team up tiles than there ever were environmental tiles, but that could've just been a fluke. It takes 12 team-up tiles to set off the move. One per tile per match, just like every other tile in the game now. If you choose a team-up, and you don't use it, it doesn't take it from you. I had 5 of BP, chose it but didn't use it, and still had 5 after the match. Leads me to believe that the count is how many times you use it... so if you were to use it 2x in one match, it would bring the count down to 3. The match was against Venom, and I got Devour as a new team-up for beating him.
The team-up tiles themselves do damage - less than top tiles for that character, but more than the 10-12 for non-specific colors. For this event, at level 134 for OBW and CStorm, they do 41 each. If you don't choose a team-up for a match, the team-up tiles just do damage. It'll be fun to play around with this new feature and see what works with certain match-ups.
EDIT: The computer gets team-ups, too, and they still try to match them first, just like they did with environmental tiles. I was facing Ares, Daken, and Rags, and I just got Symbiote Snared.