I have the constant problem with Lion, almost every DMG I try to mount gives me input/output error when verifying. Another problem I am experiencing is getting "media file can't be read" error while trying to put new music onto the iphone with itunes.
I have a mid 2009 macbook pro with Lion running on it and a new Hitachi HTS725050A9A366 drive (not sure if this is a device id or just a model). The reason why I've replaced the drive was because the original was having smart errors and Lion wouldn't install.
I don't recall experiencing these problems after installing Lion on the new HDD, it started happening recently, about 3 weeks ago.
I keep experiencing this when copying large files from the drives connected via the USB, firewire, while mounting dmg disks and while copying media via itunes to the iphone. Everything seems to be related to the long running reads / writes to the drive but I am not sure where to start looking.