After a great start to his loan period, it has been reported in various sources that Harry Redknapp is happy for O'Neil to extend his three month loan period to stay at Cardiff for the rest of the season. Icwales report here.
This would be great news, although it is to be noted that O'Neil is on a "72 hour call back" and could be recalled at any time.
There is also an article on icwales here linking in with the Pompey Carling Cup match.