This will change the character of Dailykos.
Diaries are the single channel for member's expression of ideas-- and the conversations that follow. We have an unenforced vague rule of three substantive paragraphs, but who defines "substantive" It is really defined by the group, by the expectation of a degree of originality, enjoyment and importance.
For me, one diary a day is no limit at all, as I don't have a good idea, a novel thought that I can develop into a coherent essay more frequently that that. For me, a dailykos diary is either the culmination of something I've been thinking about for quite a while, or the result of some concentrated research.
And after I've done a draft, I check it for errors, make changes, attempting to make it interesting, yet still conveying my thoughts. Then when I have it as good as I can make it, I hit the publish button. At that point luck comes into play. Will there be a slew of other diaries that push it down the list? Will the vital first comment be hostile, or will it be supportive, or better yet open up a respectful conversation.
Sometimes, I change a title, or revise the diary to make it clearer or more interesting. A Dailkos diary is only the opening statement of what, under the best of circumstances, becomes a living seminar on the issue being brought up.
Removing the one a day limit will change this. There will be a few people who will write many diaries each day, with each having the effect of dropping a more serious effort down the list even faster. Over time the serious diaries, except for those by people with a reputation here, will no longer be written. It would no longer be worth the investment in time for the diminished chance of getting a decent readership.
I fear this is the Twitter-ization of Dailykos. As the diaries become more frequent, they will be shorter, less serious---"if this diary doesn't work I can write another one in an hour!" We live in an age of ever decreasing attention span, when elections are won or lost based on 15 second ads.
It would be sad if Dailykos, the premier progressive interactive web site, becomes part of this trend.