I have accounts on both LiveJournal and InsaneJournal and am beginning to even ponder Dreamwidth despite some limitations. Posting on more than one account (same name - they are, in essense, mirrors of each other) gets increasingly annoying as the number of mirrors goes up. Naturally, I would like to automate this and have "write once, post everywhere" but I have yet to see a client that will do that. I know some sites let you (auto-re-)post to ONE other site, but I don't want to be limited.
The ideal client lets me use all the features of LiveJournal (I have a Permanent account) and InsaneJournal (another Permanent) account) so that I set the title, the text, the groups (if any), the icon, the tags, mood, etc. And both IJ and LJ get posted to and the results look identical save for LJ and IJ branding. For Dreamwidth (if I go there at all) I'd want a nice way for it to fall back to the limited icon set I'd have there, since as I understand it I simply cannot get a Permanent account there and thus Be Done with things - that's why I have those - my personal convenience.) It should also allow me to edit once and fix any goofs without having to do it two or more times. Having a selection that lets me choose to only apply a change in some places would be nice, but not essential. Oh yeah, and it must run on Linux - without WINE - and not be a plug-in to some program I seldom use, so no Firefox plug-in nonsense. While I have a Google+ account, I really only use that to read - I don't care to post there until I can use my preferred identify without Google's kiddies throwing a tantrum and potentially wrecking my phone. Also, the G+ API, like the G+ marketing department, is still in its infancy so I do not expect any current clients to properly support G+, nor do I really need one to.
So far, I have yet to see such a thing, but I could easily be overlooking something. Anything I ought to be looking at?
 Google: "It's an identity service." Really, then why can't people use theirs? Idiots.