It was speculated that the SWAT Tank from Grand Theft Auto: San Andreas was in the Beta of GTA IV, as it's handling line was still in the games files. However, there was no in-game model, and therefore no evidence that it was to be the SWAT Tank. It is unsure when the SWAT Tank was cut from GTA IV, however, it must have been quite early in development, as there is no SWAT in the game (as it was replaced by NOOSE).
The Ballad of Gay Tony
Speculation rose about the return of the Rhino (or a similar tank) in the upcoming DLC, from the first trailer, showing the DLC returning to the over-the-top style of San Andreas. In the trailer "Meet Usuf Amir" there was a glimpse of a vehicle that looked like the SWAT Tank from GTA:SA. Soon after the trailer was released, Rockstar Games released the new section of their website, detailing the vehicles of the new episode. It gave this description of the NOOSE APC: Nothing says "I've made it in this town" a like a N.O.O.S.E armored personnel carrier, equipped with a 360-degree rotatable turret and explosive ordinance.