Well, then, I'm stumped. These symptoms are too inconsistent to draw any conclusions. The videos in both albums play just fine on my PC. The one on jalbum.net takes a bit longer to start playing, because of the improper HTTP header on the file. But otherwise, it works.
I can't comment on any iPhone/iPad issues, since I have only a dumb, simple cellphone.
Video is not supported in the mobile version of albums published on jalbum.net. It does not matter which format the video has, it will not work. We will deploy an update so it will work with mp4-videos, probably early next week. If I load the url of the video (http://gerardl.jalbum.net/Video%20test%20II/GLTest_00000FS.mp4) directly on an iPhone it works just fine.
You are probably not viewing EarlyOut's album with the mobile skin, since it does not seem to have been added to his profile. That's why it works. (It will be added automatically as soon as EarlyOut visits his profile page. All this behavior is a misfeature I haven't thought of.)
PS : what do you think about AnCa's answer ?
Not having any sort of mobile device, I know little about the routine on the jalbum.net server that's geared to mobile devices. In short, if you access an album on jalbum.net with a mobile device, like a smartphone, you don't get the actual album. Regardless of the skin that was used to create the album, you get a special RSS-driven version of the images in the album. I gather it's a much-simplified display.
I host my own albums on a regular stateside host, which doesn't have any such feature. If you access a Matrix album from my host, you get a Matrix album, whether your device can handle it or not.
Complicating matters, I have the creation of album.rss shut off by default, so when I make an album, the jalbum.net server probably can't generate its special "mobile" version of the album anyway. For testing, I should probably turn that back on....
If album.rss is missing on albums hosted on jalbum.net the server will try to generate one based on the content of the album, if album.rss is requested. (It will not be stored. Only served to the client.) But the server currently only looks for pictures, so movies will be excluded.