"The term 'always-on' might conjure up visions of some sort of compelled use in which computers or applications must be left running all of the time. Always-on does not imply this; it refers merely to a characteristic of broadband networks that enables network communications to be initiated at any time. Users remain free to close software programs or shut down computers as they wish. Of course, some applications and computer devices will be designed to work best when they are always connected, and many users may choose to keep some computers or applications in an always-connected state.
"Research has shown that removing the start-up delay changes the way that users perceive and use the Internet. Because the overhead associated with accessing the Internet becomes very small, there is more casual use of the network for very short tasks &mdash sending a short message or looking up a piece of information. This change also has the effect of significantly reducing the length of a typical "session," as users begin to regard the network as an always-available utility, even though total use may stay the same or increase. Users also may change their behavior to leave their PCs on more of the time, either fully powered up or in sleep mode.
Broadband: Bringing Home the Bits, at 69-70.