I've always got huge reservations about agents acting as publishers, because agents' core function is to represent the author to the industry, and it seems to have an inherent conflict of interest if they then become the industry, as it were.

But I've long thought that one way agents' business could develop would be to help their authors to make the most of the digital revolution directly, and now Andrew Lownie, who's a much-respected agent for non-fiction who recently took on a colleague to work with fiction, is doing just that:

The difference, as far as I can see, is that he's using Amazon as the publisher, under his own imprint Thistle to get over the self-published look, to get his authors OP titles, backlist, and titles that have (say) a US but not a UK deal into print:

http://www.wordswithjam.co.uk/2013/05/andrew-lownie-talks-about-his-agencys.html

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Or even the relationship of agent and his authors' backlist...