[this is a public post on LJ]
I don't tend to do new stuff explicitly for LiveJournal nowadays, since I'm on Dreamwidth, but LJ came out with an interesting claim recently regarding the lack of a Preview button on the new commenting form:
Since a Preview button isn't easily/quickly possible with the new form, we have made the ability to edit comments available to all account types.I was honestly a bit baffled by this, because it's actually really easy to add a Preview button. In fact, I knocked up a Greasemonkey script to add one in less than half an hour, and I've never previously touched the new commenting code. (Download here. Greasemonkey script has been tested on Firefox and Chrome; if anybody else knows if it works on other browsers, let me know! To run it on Firefox, you'll need the Greasemonkey add-on. Chrome users don't need any separate addon!)
But at the same time, I don't think LJ are deliberately and shamefacedly lying, because allowing all users to edit comments is going to put a dent in their bottom line. Lots of people find the ability to edit comments incredibly useful, and there's now one less reason for people to have paid accounts.
Rather, I suspect the reason they're not introducing the Preview button on the new form is because the Preview page includes a subject line field, and they seem to be doing their best to want to get rid of subject lines. (Don't ask me why, I have no clue.)
Anyway, I mainly made this post to get this Greasemonkey script out there, because as much as I'd love people to come to Dreamwidth, there are some people who aren't going to want to do so, and being able to preview comments is kind of important. That said, if you do read this, do consider giving Dreamwidth a try. You don't even need an invite code if you sign up before the end of the year, because DW have opened up the create flow for a limited period of time. So come on over and give it a try. :)
[edit (Dec 23rd): I updated the code as there were some cases when the code would pop up a "No can do." message box - if the page wasn't using the new commenting scheme. Please download the new version.]
[edit (Dec 24th): I've learned that stuntpilot99 has made a Stylish style that makes LJ a bit easier to read by replacing the fonts with the fonts used before, slightly widens some margins, and other things. It also puts a soft grey background on everything, but as I don't like that myself, in the version I've got installed I edited it and replaced every instance of "#f7f7f7" with "#ffffff", which makes it white. In any case, go check it out. :)]