For reference: ​http://make.wordpress.org/core/handbook/design-decisions/#whitelisting-oembed-providers

Thanks for the report mt_Suzette. I'm moving this to 4.0 for consideration, although personally I do not think we should add support for Speaker Deck.

As per Sergey's link above, there are certain considerations that need to be made when deciding whether to add support for an oEmbed provider. It mainly boils down to popularity, trust, and establishment.

Speaker Deck is not a particularly popular service, and certainly isn't mainstream. It doesn't have a WikiPedia page, and it has just ~600 Twitter followers (with ten tweets in the last year). Even a search on Google for "speaker deck" only returns ~300,000 results.

Speaker Deck's parent company was acquired by GitHub in 2011, and one of their other services, Guages, was recently sold on. While GitHub is an established and trustworthy service, it doesn't appear that Speaker Deck gets much love. This brings into question whether we can trust Speaker Deck to stick around.

I'll leave this in the 4.0 milestone for now, but suggesting as wontfix. There is a ​Speaker Deck Embed plugin that can be used to embed slides from Speaker Deck.

I'm going to close this off again. Speaker Deck just isn't popular enough, and its trust and establishment aren't set in stone either. The ​Speaker Deck Embed plugin is available to those who want to embed slides from Speaker Deck.

Reopening for consideration. Speaker Deck is used quite a bit, and it's definitely a stable service at this point that GitHub continues to maintain. It's not quite as popular as Slideshare for sure, but we do have wordpress.tv embeds, which have a similar audience.

(FWIW, WordPress.com also ​supports Speaker Deck, as an added vote of confidence.)

First pass - seems pretty straightforward, but willing to accept if the regex isn't bulletproof..