Plaid Cymru is not the only party to hold a conference this week which has been ignored by the media.
The Co-operative party has been meeting in London to celebrate the party's 90th birthday. The Co-op party doesn't stand in elections as an independent political party, it sponsors some Labour candidates. We use to have a number of Co-op MPs in Wales at one time most notably former Attorney General John Morris in Aberafon, I'm not sure if we have any now. I can find absolutely no news from the conference in Google's news search, but Political Penguin has posted a couple of blogs from the event.
The Green party's get together is being held in Liverpool. With an item on the BBC and another in the Guardian, the Greens haven't been totally ignored, but given the importance of environmental issues in the current political debate I would have thought that they deserved better. The Green conference has blog coverage in Another Green World.