On my occasional trips to London, I would purchase a one week Zone 1/2
Travelcard, slip it in with my LT Photocard and be covered for most of my
transportation needs.

With the advent of Oyster, I'm not sure that's the preferred way, or even
possible anymore. Assuming I would need to be in London once a year or so, what
would be the best ticketing solution these days?

Thx