I've just released a new LiveJournal client for Windows, called MultiLJ. Its defining feature is that the user can open as many windows as they need - journals, profiles, post editors, and so on - and they will be hosted internally within the program. There is no dependency on the user's default browser, nor is the user limited to writing only one post at a time. Editing and deleting past entries is fully supported, as is management of custom friends groups.
The client is new, so I consider it beta level - I'd appreciate as much feedback and error reporting as possible. THere is a support community at multilj, which is also where the link to the download page can be found (on the profile for that community).