I've tried to download an .apk file via OTA, and all the device does is to show the binary characters instead to download file.
But I tried to download apk files from this forum, for example, and it worked perfectly. E.g. links present on this post: http://www.anddev.org/get_your_android_application_tested_on_a_g1_-t3063-s45.html are downloaded perfectly and runs normally. But if I take one of these apk files and put it in a personal server G1 device does not open the file, it shows binary characters. Why that?
If you want I can give you a link to test it.