Central twisted transformation groups and group $C^*$-algebras of   central group extensions
  We examine the structure of central twisted transformation group \cs-algebras $C_{0}(X)\rtimes_{\id,u}G$, and apply our results to the group \cs-algebras of central group extensions. Our methods require that we study Moore's cohomology group $H^{2}\bigl(G,C(X,\T)\bigr)$, and, in particular, we prove an inflation result for pointwise trivial cocyles which may be of use elsewhere. 
Siegfried Echterhoff (Westf\"alische Wilhelms-Universit\"at   M\"unster), Dana P. Williams (Dartmouth College)