As I said it's still quite buggy atm.

I find it ultra impossible to track downloadable games, Dude!

as far as i am aware it is impossible, but that is why im going to ask about it because if they found a way that would be great.

450k seems kind of low for Journey considering the reviews/hype it was getting and the amount of GOTY awards. If 450k is true then I am a little disappointed.

Again it's "just below 500k" and not 450k.

Then you're only disappointent because you probably never really looked at other digital sales data and if you did it was most likely Steam data. Digital game sales on PC are far far far more important than on PS3 and 360.
Seriously many indie games have the opportunity to sell a million copies on Steam (without Humble Bundle). On PS360 those would be lucky to break 300k.

Therefore 500k is really good in not even 12 months. Don't know if it will ever get to a million since the gen is almost over, but 700k or 800k is guaranteed.

It is just under 500k. I read something wrong.  And 500k is amazing for an arcade titles so dont be dissapointed.  That means it is the 4th best selling arcade game this year.

Exactly. Limbo had 580k leaderboard entries on XBLA at the end of its launch year (2010) and managed to break the 1m mark only a few months ago.

http://www.gamasutra.com/view/news/123141/InDepth_Xbox_Live_Arcades_2010_Sales_Revealed.php#.UQ8KE2evBuY

http://gamasutra.com/blogs/RyanLangley/20121011/179195/Xbox_Live_Arcade_Sales_Analysis_September_2012.php

750k for Journey at the end of this year is likely and a very good result.