The distinction between ``connected words'' and ``continuous speech'' is somewhat technical. A connected word recogniser uses words as recognition units, which can be trained in a isolated word mode. Continuous speech is generally associated with large vocabulary recognisers that use phones as recognition units and can be trained with continuous speech.
Many researchers working on interactive dialogue systems wish to use the notion of speech act without enlisting the whole philosophical apparatus of Speech Act Theory [Austin (1962), Searle (1969)]; for this purpose the term DIALOGUE ACT has been coined and is steadily growing in acceptability.