Long domain names aren't good as a rule of thumb just because you don't want people to have to type a bunch or risk misspellings. On mobile devices especially,

Long domain names aren't good as a rule of thumb just because you don't want people to have to type a bunch or risk misspellings. On mobile devices especially, the less you have to type the better. That said, domains like icanhazcheezburger.com clearly work effectively...so there are exceptions to the rule. More important that what comes first, might be what comes last in your domain name. At least on Android, you have a shortcut key for ".com" which elevates the importance of having a dot com domain because it makes them easier/quicker to input.