Eclipse uses the latest release of Ant – deadline round about March or May of the year. So I hope that Ant 1.7.0 will be part of Eclipse 3.3 and therefore of MyEclipse 6.
BTW – you could build an Eclipse plugin of the Ant manual with Manual4Eclipse [1]. I think I will upload the 1.7.0 and HEAD manual …
[1] http://svn.apache.org/repos/asf/ant/sandbox/antlibs/manual4eclipse/