As for how we've been getting the data from the missing chapters, we've actually been getting it two different ways. Every month in the manga discussion forum there is a "____ Plot Discussion" (____ stands for whatever month it is, but how the titling work is it's always this month's plot discussion always had next month in the title. Like for example, it's now April but instead of the April Plot Discussion, this month's discussion is called the "May Plot Discussion".) and the thread will talk about 2-3 chapters released during the month. Sadly we don't get to read all the chapters online, just the one that /a/non does every month, but sometimes people will give detailed summaries of what happened in the chapters and tons of pictures from the chapters as well, so that ties us over and give us info about the other chapters until we get to read them one day. The second way we've been getting information (well, more of pictures of the chapters than actual information) is via the official Japanese Pokemon Special website, here: http://family.shogakukan.co.jp/kids/netkun/pokemon/official/ If you click on the second box on the first row (on the set of boxes in two rows on the bottom of the page) then a different page will pull up and you can scroll up and down and look at all the pictures from this month's chapters. (it gets updated the first day of every month) And that's how we've been getting the data on all the other chapters. Hope that helps.
Oh, and here's a thread that has compiled the summaries (when they were given) for all the Black/White chapters out in Japan so far. http://www.serebiiforums.com/showthread.php?t=476861 Hopefully that'll help some for now, and then later I can find the older threads and tell you what happened in the chapters of months that don't have summaries for the chapters, as well as give you links to all the pictures we got from all the chapters if you'd like.
I'm glad to hear you've become addicted to this new chapter of Special as I have too; and I'm sorry to hear that you've only seen 5 chapters of it. I'm glad you asked though because you definitely came to the right person about it. I'm guessing the 5 chapters you've seen are from /a/non, and if so let me explain a little bit about that first. You see, the Black/White chapter of Special started last...October I believe, and since then 2-3 new Black/White chapters have been coming out every month now via two-three different magazines (one chapter per magazine; and the number of chapters varies between 2 and 3 each month). The reason you've only been able to come across 5 chapters of it though is because the guy who's translating/scanning the chapters online, /a/non, is only doing chapters from one of the three magazines the Black/White chapter is being released in. Because of that, he's only doing one chapter a month hence the missing chapters. That said however, he should actually have a couple more chapters than just 5 out though; but he started a month or two after the Black/White chapter started, and he never bothered to do the old chapters from the time before he started hence the rest of the missing chapters.