The Wayback Machine is kind of like a video tape of the vast majority of the Internet's history, capturing probably too much for posterity, but such are the times we live in.
I don't know what the copyright situation would look like, but why wouldn't Google (or someone else) offer to make it keyword accessible? It could conceivably be sold as a service to law firms, pr firms, media, and anyone else interested in paying for that kind of capability, or have ads attached to search results or both. Though being a non-profit Wayback might frown on such behavior, and I imagine that's why it hasn't yet happened.
If that's the case, Google should just donate the capabilities and maybe even the developer resources to make it happen. It'd be a PR win that supports their mission and adds polish to the "informal corporate motto, 'don't be evil.'"