To see two preview clips from tomorrow’s Doctor Who finale, click here and scroll down to “The Wedding of River Song: Previews: Reveal” – not to be confused with “The Wedding of River Song: Introductory Videos: Reveal.” (There’s other cool stuff there too.)
To say that these previews involve SPOILERS would be an understatement. In fact the mere still images displayed before the clips start playing contain spoilers, which is why I haven’t embedded them here.
Later tonight I plan to offer some speculation in the comments section here, so for those who find mere speculation spoileriffic, stay away from the comments section.
In the meantime, check this out if you dare. Its content isn’t spoileriffic (as it’s about 1970s Who), but my linking to it in this context might be.