Fresh rumour from erlang-questions OTP is working on xmlerl improvements, leaked by Kenneth Lundin at OTP himself:
We are working on significant performance improvements and new API’s for XMERL.
The new XMERL will be at least 4 times faster than the current version. The base for this is a completely new SAX parser that you also can use directly with new API’s.
The memory consumption will also be significantly reduced.