Whether by design or not, the new Sidisi works well with Sidisi, Brood Tyrant, especially in Reanimation based decks that will now feature them both. Having a 4/5 creature with deathtouch that can also serve as a tutor. is certainly handy. She's definitely strong enough to see Constructed play.
In Commander, Sidisi, Undead Vizier will be even more useful, as it's a format where tutors are extremely important. There are many ways to create sacrifice outlets in Commander, especially in Mono-Black where Sidisi could serve as a solid Commander or complement to a wide variety of strategies. On top of all that, Sidisi is even a Zombie, an extremely well-supported creature type, making her even more versatile. Mono-Black continues to get more powerful and Sidisi continues the trend.