Ok, this is a pretty basic thing about Twitter usage that I seem to have to point out quite often - thus, a post that I can link to easily.
To make it very blunt: Don't start tweets with an @, unless you intend it to be a very narrow audience. Why? Because if a tweet starts with an @ symbol, they will only show up in the timelines of:
This is so that people can see conversations between two people they follow, without flooding your timeline with conversations between those you follow and anyone else.
Alright, so why am I raising this issue? Pretty simple, really. Tweets about your stuff. Your promotional tweets - make sure they aren't narrow audience limited.
If you must form a tweet this way, place a full stop in front of the @ so it's not the first character - but don't do this for normal conversation. It invites dogpiling and is seen as shitty behaviour in general
I am pretty well known for having conversations on twitter with myself - or appearing to do so. When I have a few thoughts longer than a single tweet, I will write the first one, then reply to it (and leave my name there), then carry on. Many people have gotten in touch with me to let me know 'you can delete your name from the second tweet, it'll stay linked' - and I need to politely respond: You are incorrect on a number of levels.
Let's run through a few things quickly:
The first point here is obviously the most important - some clients will preserve a context link, but most won't. Some will for version X but not the next version. TweetDeck, which is a twitter owned client, is very different in experience to the twitter site. Even Plume has some odd behaviours about linking tweets together via replies that are only implicit rather than explicit.