Recent anycast developments in the IETF are:
in IPv6 anycast addresses are allocated from the unicast address space with unicast address formats [RFC 3513]; Deering and Hinden [RFC 2526] "defines a set of reserved anycast addresses within each subnet prefix, and lists the initial allocation of these reserved subnet anycast addresses." Please see our survey of anycasting.
Some notable non-IETF anycast related works are:
the implication of an anycasting service supported at the application layer was explored in [1]; a new anycast routing protocol was developed in [2]; a framework for scalable global anycast was proposed in [3].
[1] Ellen W. Zegura and Mostafa H. Ammar and Zongming Fei and Samrat Bhattacharjee, "Application-layer anycasting: a server selection architecture and use in a replicated Web service", IEEE/ACM Transactions on Networking, Vol 8, Number 4, pp 455-466, April 2000
[2] Dong Xuan, Weijia Jia, Wei Zhao, Hongwen Zhu, "A Routing Protocol for Anycast Messages", IEEE Transactions on Parallel and Distributed Systems, pp. 571-588
[3] D. Katabi and J. Wroclawski, "A Framework for Scalable Global IP-Anycast", In Proceedings of ACM SIGCOMM, Stockholm, Sweden, pages 3--15, August 2000.