So Foursquare has started to use NFC: Foursquare NFC checkin. This sounds like fun :-) I guess you can't seriously do harm but pranks sound possible.
Moxie is really cracking out cool Android stuff lately. He just released WhisperMonitor a personal firewall for Android.
Slides for the Android Attacks talk from Infiltrate. Really really good and complete talk on Android security.
Usenix Security 2011 has a few interesting looking papers: Forensic Triage for Mobile Phones with DEC0DE by Robert J. Walls, Erik Learned-Miller, and Brian Neil Levine, University of Massachusetts Amherst. Secure In-Band Wireless Pairing by Shyamnath Gollakota, Nabeel Ahmed, Nickolai Zeldovich, and Dina Katabi, MIT. A Study of Android Application Security by William Enck, Damien Octeau, Patrick McDaniel, and Swarat Chaudhuri, Pennsylvania State University. Permission Re-Delegation: Attacks and Defenses by Adrienne Porter Felt, University of California, Berkeley; Helen J. Wang and Alexander Moshchuk, Microsoft Research; Steve Hanna and Erika Chin, University of California, Berkeley. QUIRE: Lightweight Provenance for Smart Phone Operating Systems by Michael Dietz, Shashi Shekhar, Yuliy Pisetsky, Anhei Shu, and Dan S. Wallach, Rice University.
The Black Hat Vegas CFP is still running. So no talks posted yet.
I spotted two talks at Virus Bulletin: An OpenBTS GSM replication jail for mobile malware by Axelle Apvrille Fortinet and Android malware is on the rise by Timothy Armstrong and Denis Maslennikov.
That is it for May I guess. Since I'll be either traveling or writing papers ;)