The music service is now recognised by 82% of all US downloaders, placing it in first position ahead of rival , which is recognised by 76% of downloaders, according to the Ipsos' Tempo Digital Music Brandscape study.
An emerging majority, 50% of US downloaders who are aware of more than one site, consider the best fee-based digital music service, which is up from 41% in 2006.
, which is in second place, is rated "best" by just 10% of the downloader market, a figure that did not change versus 2006.
In third position is , rated "best" by 6% of downloaders, followed by with 5% and and , both with 4%.
Karl Joyce, senior research manager of Ipsos Insight and author of the Tempo study, said: "iTunes' steady gain as 'best' brand over the past three years does denote a threat to other digital music services, particularly due to the persistent lack of inter-operability.
"While iTunes' growth in 2006 may have come at the expense of Napster, other brands have begun to feel its impact as well, including other top competitors such as Rhapsody and Yahoo! Music.
"Moreover, social networking's hope of overtaking the lead in mainstream digital music acquisition appears to have fallen short."
Ipsos reported that MySpace has lost ground over the past year -- MySpace's perception ratings declined across a number of attributes as its awareness increased.
The social networking site is reportedly recognised by 60% of US downloaders, however only 1% of these people think of the brand on a top-of-mind basis.
The sample size of this study was 1,826 internet users. It is the fourth annual Tempo Digital Music Brandscape study, which examines fee-based online music brands.