Are Memes (in Dawkins's Sense) Alive
Important other case: are memes in the internet lolcat sense alive?
Note that the Stanford Enyclopedia of Philosophy is wonderful, especially for philosophy of science (although it doesn't always have an entry for what you want).

A lot of the arguments against memes are comparing them to popular definitions of genes, but we can be more sophisticated than most people about definitions of genes.

Memes are very vague. And genes are also vague (at least, in Dawkins's view). But a big difference is that we know for sure that genes are useful for explaining lots and lots of things, in detail. I don't think memes are like that. They're just tooooo vague.

Think about recipes. Disanalogies from genes:

But despite all those disanalogies with genes, memes do reproduce and have their own sort of evolution. So are they alive?

If they are, they can't exist on their own - they can only be parasitic or symbiotic. (By the way, they might be analogous to Feinberg and Shapiro's self-organising system, which came before biology on Earth, according to them.) But not only do memes depend on us, they also physically overlap with us - and that IS unusual. No cellular life ever overlaps with other cellular life - a cell always belongs to only one organism. (That's not clearly the case for viruses, though.)
Memes are alive if they co-exist with other life ? (memes rely on other life to exist). They also rely on other life to mutate.

If memes are alive, than the innovations that "intelligent life" have come up with are not actually from us, they are simply evolved memes.

Extreme meme case: We can conceive of a meme that is sufficiently powerful to hijack the brain and hence body of an organism. Could it spread itself? A fundamental limitation would be whether neural architecture is sufficently similar for an idea that can hijack one person's mind to hijack another. In such a case, surely we can imagine that such a meme could be alive, with generations (individuals infected) and mutation (changes to the idea allowing it to infect more minds).

Problem: Internal experiences of ideas are variable, (extreme case, between ppl with different native languages) and even if two people share an idea, and they really do have the same idea (the blue that I see really is the blue that you see) their experience of the idea will still be experientially different. Is it different enough that the meme couldn't be said to be the same thing between the two?

Chemicals aren't alive just because humans are, but a collection of chemicals could be alive.

Tentative conclusion: a meme (or a collection of memes) could be alive in principle, even if none of them currently are.