I ordinarily have no problem with changes in usage, semantic drift, and whatnot, but the literal/metaphorical thing bugs me. We don't appear to have a replacement for what literal used to mean. When I wish to say that something really-actually-totally-seriously did happen, no lie, I no longer have an easy way to express that. Not only is literal used to describe something that isn't literal, it's also used to describe what metaphorical used to cover. Metaphorical, on the other hand, rarely appears in speech. All of this leads to obfuscation of meaning. So, when a friend tells me, "He literally fucked me," I don't know whether they mean that there was sexual penetration, or whether they mean a different sense of fuck. Without literally, I'd know they didn't mean sex. Perhaps when people stop using literal in its old sense, I won't have to think about the difference anymore.
The same can be said about irony/coincidence/randomness. People say, "That's so random." Well, no, whatever they're talking about usually isn't random at all. Instead, it's usually a coincidence. Certain articles and brands of clothing worn by yuppies are usually not ironic. You'd expect a yuppie to wear shit like that; it's the opposite of ironic. And you almost never hear coincidental at all.