An official chart of the UK's most popular music downloads is being planned by the people who compile the top 40 singles chart.
Chart star Daniel Bedingfield is fronting Digital Download Day
A new top 40 of tracks downloaded from official sites is planned to be in place in time for the Christmas number one race.
And downloaded songs could count towards the main top 40 chart within 18 months.
"It's very important for the singles chart to remain relevant," a spokesman for the Official UK Charts Company said.
"If a new format is generating considerable sales we have to pick up those formats as well as the more traditional forms. It's a major initiative for us.
"Downloads will be incorporated into the official singles and albums chart. It will happen when the music industry is ready for it. We're probably talking about 18 months."
It will only count songs paid for on certain legal subscription sites rather than the more popular but illegal fan sites like Morpheus and Kazaa.
The plan was announced to tie in with the second Digital Download Day on Wednesday, when UK and German music fans have the chance to download music from legitimate sites for free.
The download top 40 will be compiled by the Official UK Charts Company and endorsed by the music industry, according to digital music service OD2.
It will count tracks downloaded from websites including those that use OD2's catalogue of 170,000 tracks from more than 7,500 artists from Eminem to Michael Jackson and Gareth Gates.
That catalogue is available on sites like MSN, HMV, Freeserve and MTV.
A one-off chart for the favourite tracks on the second Digital Download Day will be released later this month.
The second Digital Download Day gives UK fans access to £3 of free music, allowing them to download 30 tracks, stream 300 tracks or "burn" - or copy - 3 tracks to blank CDs.
It is also Digital Download Day for German fans, who get 5 euros (£3.50) of free songs and similar campaigns have recently been held in the rest of Europe.
The first day, in the UK in October 2002, was deemed to be a success in persuading users to abandon "pirate" services that are thought to be damaging the music industry.
An estimated 4,500,000 people are thought to be downloading up to a billion pirated tracks over the internet at any one time.
This Digital Download Day is being fronted by chart star Daniel Bedingfield, who said: "Digital is the future of music.
"Every record needs to be available legitimately online before things can really take off. A superior choice of tracks is fundamental to a defence against online piracy."
UK culture minister Kim Howells said internet piracy could do "great damage" to the music industry.
"We have to think smart and harness new technology if we are to tackle piracy effectively and use initiatives like Digital Download Day," he said.