NetNewsWire? Archipelago? Kung-Log? There are many ways to escape the suckitude of writing in a web browser...
So I'll give these another try - my first looks at this kind of application a while ago were rather unsatisfactory, making an unpolished impression and not being much more comfortable than a web browser. Now, of course, Safari has raised the bar a bit higher by including spell-checking in its text-fields that Chimera lacks.
I am just typing this in NetNewsWire's non-light beta version - and it feels quite good - I can see my previous posts and apparently correct them, HTML and links in my text are highlighted and there is spell-checking, which - a nice touch - doesn't mark HTML or URLs as wrong. The typing of text seems to be lagging a bit, though. Probably the code hooking in the text system to highlight the text and modify the spell checking isn't quite optimal yet. I hope they'll resolve this. On the downside, there are specific buttons for bold and italic text, which is probably bad style, and a link button the use of which - including a sheet - seems vastly less efficient to me than typing the appropriate HTML myself.
I would favour NetNewsWire, because I have a copy running anyway to read RSS feeds. I also like the Notepad feature the non-light version offers. The UI still needs a lot of refinement, though:
Received data seems to be invalid. The wanted file does probably not exist or the guys at last.fm changed something.