Hi Peter,
Unfortunately by default, it will show the "Primary" column of the entity and at this stage there is no way to customize that.
In your case, the Primary column of the account entity is the Account Name.
I hope this helps. If my response answered your question, please mark the response as an answer.
Dimaz Pramudya - CRM Developer - CSG (Melbourne) www.xrmbits.com http://twitter.com/xrmbits