Transport Tycoon Forums

... but could I just check something here? A long time ago, I used to play OpenTTD, and the last official build I think I downloaded was 0.4.8. Back then, noAI was a separate OpenTTD build whereas the main build came with the 'crappy old AI'. Am I right in thinking that noAI has now been incorporated into the default build and I don't need to go fishing for a separate build to get the noAI functionality?

yes

Also you can click the "Check online content" button in the main menu window to get a list of AIs/GRFs/scenarios etc. that is available for download from within the game. This service is called "BaNaNaS". Most AIs are added to bananas for easier download and the game will automatically select and download necessary AI libraries as well.