I am honestly too nervous about the book launch on Saturday to come up with anything interesting to say, so I'm going to push on with a terms clarification about the different types of publishing.
Publishing: These are the huge publishing houses like Hodder and Stoughton, who do offset printruns in the thousands, and probably release as many promo copies as a small press expects to sell in total. This is what most peple think of when they mention "Published". Some people also refer to this as "traditional publishing".
Self publishing: You personally own the ISBN, or have set up a company purely to publish your own works. Nowadays this usually involves lulu or createspace, to make the books available through POD, or using Smashwords or Amazon to publish as e-books. Unfortunately with no quality checks, while most authors deliver very good work, it also possible to take an unedited unformatted word file and release it in exactly the same way. For readers it can be difficult to tell the quality of the book, which is why reviews are important and why self-publishing has a questionable reputation.
Small press: May use a small offset run or POD (sometimes the same providers as the self-publishers) but have staff who can do cover designs, editing, typesetting etc, like the larger ones. Many university presses fall into this category. There are also an increasing number of e-book only small presses. Often these will focus on one area or special interest such as poetry. They don't pay as much as the larger houses, but as they can choose their manuscripts they do offer readers an assurance of quality which is missing from debut self-published works. Small Presses are often called "Indie presses", although that term has been co-opted by people who fall into the group above.
Vanity Press These are companies that allow an author to pay for their book to be published. Don't confuse these with printers, as they normally sell publishing packages. Some are reputable, some less so. Some provide good service, others don't. Recent spins on this are "subsidy publishing" where the author contributes to the cost, or "reverse vanity" where they buy your book, but then charge for formatting, layout etc. or commit the author to buying copies. As with any service, if you intend to go this route, you need to research it carefully, and authors who use it are rarely considered "published" by the trade.
For self-published books and vanity published books, there is rarely a quality check: if an author has the money they can publish. This unfortunately means that some very bad books get published as well as some very good ones and results in readers being somewhat wary. Also, because the manuscript did not go through the peer-review of small press or mainstream publishers, authors going this route have much higher odds to overcome before they are considered published - often when a mainstream house offers them a deal.
Regarding Fire Season, Ragged Angel Ltd publishes several other authors, and has commissioned work for hire before. The Principia Malefex RPG line is already in print from them, and has been available since 1996. Fire Season was launched largely through those channels in the same way an RPG would be. By mainstream print standards it is a very small press. It is also the first Kindle title for this publisher, and the first mainstream fiction title.
The fact that Ragged Angel are a games publisher first however, brings me back to Salute and the fact Fire Season is getting launched at a very large games convention in less than a week. A fact I am trying not to think about.
If you will excuse me, I'm off to the pub to drown my nerves!