I recently stumbled upon
a fascinating survey of 21st-century classical music (click on "Get more information") from 113 leading conductors, critics, art directors, and musicologists in Europe's contemporary music scene. The results unsurprisingly seem to skew toward a similar avant-garde aesthetic, that of the so-called "Third Viennese School", but I still find them to be rich with recommendations.
I've incorporated all the relevant results in my current tallies, thus bumping up the following works:
Abrahamsen: Four Pieces for Orchestra (now listed)
Adams: The Gospel According to the Other Mary (now listed)
Adès: In Seven Days (now 2-star)
Berio: Piano Sonata (now listed)
Boulez: Dérive 2 (now 3-star)
Chin: Le Silence des Sirènes (now listed)
Furrer: Enigma I-VI (now listed)
Furrer: FAMA (now 3-star)
Gubaidulina: Glorious Percussion (now listed)
Haas: Atthis (now listed)
Haas: dark dreams (now listed)
Harvey: Speakings (now 2-star)
Kurtág: Colindă Baladă (now listed)
Lachenmann: Concertini (now 3-star)
Lachenmann: Schreiben (now 2-star)
Murail: Terre d'Ombre (now listed)
Rihm: Dionysos (now 2-star)
Rihm: Sieben Passions-Texte (now listed)
Saariaho: Laterna Magica (now 2-star)
Van der Aa: Blank Out (now 2-star)
Van dar Aa: One (now listed)