Sources say that the White iPhone 4 will actually launch tomorrow. Tomorrow marks the beginning of the Macworld expo. The Apple store is also currently down for updates which could also be for the White iPhone 4 release.
Apple originally said that the White iPhone 4 would launch by spring 2011 so we are not that far off. However this is not official nor confirmed but it is very likely and very Apple like.
Update: Tweet found to say it as well.
Looks like the white iPhone is finally coming… Today! MC604X/A (16GB) and MC606X/A (32GB). Thanks Mr X.
Update: The store came up with a new design and no white iPhone yet, however international sites have a white iPhone in the gallery.