I was talking to some PhD students here recently about the relative merits of submitting their work to Conferences or Journals - a typical chapter of a thesis makes a nice paper
before you write the dissertation, it is nice to have it published in paper form, but to get the process done and dusted before the PhD examination comes along, you almost certainly have to send it to a conference rather than a journal because of the turnaround times - its 6 months from submission to presentation for typical top-league conferences, and more like 2 years for the equivalent conferences in Computer Science.
Reason for publications: confidence boosting (for student AND for examiners:)
and feedback is useful to improve work even if it doesn't get in...
Plan B (if things work out) is to submit a 9-12 page version to a top conference, get your PhD and submit the 12-20 page version to a journal after....reason for submission: archival version (maybe) and certain academic communities' career paths still value journal higher than conference (mostly, though, citation is lower...)
Some points to consider though
1. academics or industry research lab workers do all the work for conference and journals (run submission sites, do reviewing, do editorial work, do selection, do a large part of conference organisation etc etc)
2. a typical top class journal or conference paper represents about 1MY effort - typically if you include all the effort by a PhD student for a year, plus their advisor and any co-authors - in systems, it can be as much as 2-3 people's work
3. a typical conference reviewer might look at 20 papers in 30 days - so if they are really really insanely fast at reading, and on top of all the latest material (and not handing it out to their poorly as yet calibrated own students to review, or at least only doin this to help their students get calibrated or give them up-to-date feedback, but still doing the review themselves) if you are lucky, your paper gets 4 hours work on it at a conference
4. a journal submission might get a rainy Sunday first submission, and then several hours more over revisions, so you get a lot more detailed care and feeding in the process.
5. In my experience, examining a PhD takes 3 days work - if you consider the naive equation, that 1 dissertation is == 3 good papers, then this is about twice the level of attention a paper gets (at best)
6. Finally, a lot of researchers use long journeys to read a lot of papers (transoceanic flights are good) - this appears to have stalled for the last few days around this part of the world - I wonder what impact this will have on conference review quality?
On the other hand, maybe the mortorium on flying will reduce the number of weak or nearly pointless workshops ...who knows...