That would be awesome

[Divinus7]

Since they updated the core of the wotlk realms and made alot of working dungeons/raids it would be really fun and would be AMAIZING if they would do the same thing to the cata realms. That would bring so much content to the cata realms and alot of new transmogs,raid runs, etc....
Please if it could happen, make it happen

[Islingr]

this post should still be accurate even tho the timeframe for them is different than it used to be

additionally

Several high priority class fixes have been implemented over the last few weeks. These fixes included exploitable spells such as ignite and item sets, as well as fixes to pet AI and raids. Now that early content preparations on Lordaeron come to an end, we have started porting of vanilla and tbc instances to other patches. Molten Core, Zul'Farrak and several 5 man dungeons will be amongst the first ports to be introduced on Cataclysm once implemented.

so to answer your question... yes we are getting content... no guarantee this old devlog is still accurate, but safe to assume that if work on said instances did in fact start, it would make sense to continue working on them and release them as planned