Answer:

Raiser's Edge NXT maintains full backwards compatibility with Omatic products. Raiser's Edge NXT is only available in Blackbaud Hosting (there is not an on premise option available). As a result, Omatic products that are supported in the Blackbaud Hosting environment are fully compatible with RE NXT. 

Omatic products available in Blackbaud Hosting & compatible with RE NXT: 
ImportOmatic, List Management, SegmentOmatic, RecordRadar, FindOmatic, PostOmatic, EventOmatic, MergeOmatic, and ScoreOmatic.

Omatic products that are not supported in the Blackbaud Hosting environment are not available with Raiser's Edge NXT at this time. We hope to gain approval for these products in the Blackbaud Hosting environment in future, which would make them available for use with Raiser's Edge NXT.

Omatic Products not available in Blackbaud Hosting (and therefore not available with RE NXT) include: 
ActionOmatic, QueryOmatic, Magic Folder

What about Blackbaud's new API?
RE NXT will deliver REST-based APIs in the future for customers and partners to use. As the new API becomes available, Omatic will explore opportunities to take advantage of the new API. In the meantime, the existing API from Raiser's Edge 7 remains compatible with RE NXT.