I agree with thereuare that it's probably either Vdara or Cosmopolitan. However, I'm looking at my own dates (1/8-1/11) right now and notice an additional hint based on the following options:
5-Sar Express Deal Hotel: $85
Las Vegas Strip South
5-Sar Express Deal Hotel and Casino: $97
Las Vegas Strip South
Vdara is a non-gaming property, so it is likely the $85 option. Cosmopolitan (which has a casino and is generally more expensive than Vdara) is probably the $97 option. This is reaffirmed by the room choices, as the $85 property offers a "Vdara Suite".
Both properties charge a resort fee of about $35/nt, and both show the "Additional Mandatory Fee" of $117.60 (which equates to $35/nt +12% tax) on the price roll-up. My best guess is that Priceline doesn't forecast resort fees for some hotels if the booking is far in advance, as resort fees increase annually and are collected at the time-of-stay. The other guess is that they've "fixed the glitch" during the past week.
In short, the "and casino" designation (or lack thereof) is a helpful hint. Off the top of my head, non-gaming properties on the strip include:
The Delano
The Signature at MGM Grand
Vdara
Trump
Elara (Hilton Grand Vacations)
I doubt these will ever be a PRICELINE EXPRESS Deal on Priceline, but for the sake of completeness: The Four Seasons and the Mandarin Oriental
