I recently noticed that the banner signs over the staircase entrances at
the junction itself have been replaced with displays which just say
"Oxford Circus Station" 99% of the time but are effectively
ultra-wide-screen TVs capable of displaying any message. How new are
they? Is this the only station which has them? I presume they have an
"Emergency - Don't Enter" message as well, but what else will they be
used for?