There's a lot of documents on the web that has mis-interpreted the name of the product with some of the variations you could see in the title of this blog itself! When I do a Google on "TXSeries" it's always the standard information from the product's site... I don't tend to see any discussion out there in the community, but a small tweak to the name, like "TX Series" +CICS produces some amazing results... give it a try!
I guess, the correct representation of the product name is "TXSeries" (the first three letters in capital) ... or to be more precise "TXSeries for Multiplatforms" as seen in the IBM's site.
So few tips if you are searching for any content related to this product. Use different variations of TXSeries like TXSeries (the correct one, unfortunately with less search results), TX Series (the most commonly used 'incorrect' representation), and so on. And a magic happens, and your search results gets more precise if you include the "CICS" word in your search.
I have heard this product getting referred to other names like CICS on open systems, CICS on distributed platforms, CICS open, CICS 6000, CICS on AIX... So if you are not finding any results with your searches, you might want to include some of these terms and try again.
If you still can't get relevant search results, may be that's something not yet discussed on the web, so you might want to try discussing it here: TXSeries Forum
So, happy searching! and you have learnt your first lesson on TXSeries!