Thanks to the launch of Amazon’s Cloud Player, Google Music and Apple’s iCloud, we have written a lot about cloud-based music lockers lately. According to the latest data from online analytics service Compete, however, Amazon’s Cloud Player – which is the only one of these that is widely available today – has not been able to amass a large user base yet. Until the middle of March, Cloud Player saw about 250,000 unique visitors per week. According to Compete’s data, the service wasn’t gaining a lot of traction though, until Amazon started to promote it in the context of its $0.99 Lady Gaga promotion. That promotion alone brought about 150,000 new visitors to the Cloud Player – a 63% increase in traffic from the previous week – though it remains to be seen if these people will continue to use the service in the long run.

Overall, though, 400,000 unique visitors per week isn’t a massive number, especially given that Amazon has put a lot of its marketing power behind the Cloud Player. In the world of streaming music, where companies like Pandora have about 80 million registered users in the U.S., 400,000 unique visitors per month is not a lot.

Interestingly, Google’s Music service – which is still in an invite-only beta – attracts about 50,000 visitors every week, though very few of them are likely to even be able to use it. That points to a strong interest in this service. Spotify, which hasn’t even launched yet in the U.S., sees about 50,000 unique visitors per month from the U.S.