Problems with particular services
As well as general problems, each existing service has its own problems.
- has a 140 character limit, doesn't allow long messages with multiple paragraphs
- no text markup (bold, italic, etc.) or paragraph-level markup (different levels of heading)
- no embedded YouTube.
- It's hard to see the context of a post, for example you can't display a thread containing a group of posts
- is controlled by one company and is not an open protocol that everyone can use/extend
- The twitter website takes 100k to load which is a ridiculously high overhead for a 140 character message
Usenet is text only and, probably because of this, is in terminal decline.
There is no good way of quoting previous messages, particularly when you have multiple levels of quotes (nested ">" stop working properly when lines overlap the 78-char limit).
On many Wordpress installations, the screen to write a new message takes a long time to come up, and behaves sluggishly.
Wordpress uses two separate, but related concepts of a category and a tag; since they basically implement the same idea, they should be subsumed into one concept.
Wordpress's wysiwyg editor is sometimes error-prone.
Conversations aren't threaded. So in a conversation with 20 messages, there could be separate threads and it's had to see what messages a particular message is replying to.
phpBB uses it's own idiosyncratic markup format.
Facebook is a centralised system, controlled by one company that seems to want to replace the open internet with an AOL-style walled garden.
Replies to a Facebook post aren't threaded, i.e. you can't mark a post as being a reply to a particular reply.
The user interface is too complicated.
There is no privacy: because individuals' private data is stored on Facebook's servers, governments can get Facebook to reveal it to them.
Gmail works fine when you have a good net connection, but not when the connection is slow or unreliable.
Doesn't have threading.
Your data is stored unencrypted on a central server, thus governments can get at it.