I've added drag & drop support for Tellico in the current 1.3 branch and SVN trunk. What that means is that you should be able to drag a bibtex file, or any other type of file that Tellico supports, into the main Tellico window, and have that file imported. There are still a few rough edges, notably what to do when multiple files are dropped, but the framework is there.
Also, I've implemented an importer for PDF files. If available at compilation time, Tellico will link to the Exempi and Poppler libraries for reading PDF metadata (XMP, if you will). If your PDF file has metadate such as title and author, then Tellico should read it. So now you can drag a PDF file into Tellico, and have it be imported as a new Bibliography entry.
Exempi and Poppler are optional build dependencies, by the way. They are not required.
There will probably be a version 1.3 release, which does not use a SQL backend. I just haven't gotten SQL working yet, it's as simple as that. And there are some itches I'd like to scratch now instead of waiting. Some of them are involved with better bibliographic support, and reading PDF files is one item on that list. Another is supporting DOI identifiers. I hope to have time to work on that this coming weekend.