I just got around to looking her up, and she seems to have been quite a figure in literary circles. (And it seems she was the artist in my new/old volumes.)
From The Letters of Robert Browning and Elizabeth Barrett Barrett, 1845-1846 Vol. 2
"I like Mrs. Jameson nevertheless --I like her more. She appreciates you--and it is my turn to praise for that, now. I am to see her again to-morrow morning, when she has the goodness to promise to bring some etchings of her own, her illustrations of the new essays, for me to look at." (p5)
"Mrs. Jameson came late to-day, at five--and was hurried and could not stay ten minutes, but showed me her etchings and very kindly left a 'Dead St. Cecilia' which I admired most, for its beautiful lifelessness." (p. 9)
I also found her Shakespeare's Heroines and a rather dense theoretical piece on her that also includes a brief biography. It claims that in the 1820s and 30s she was "one of the first women to make a reputation ... as a multi-faceted professional writer". A biography of Jane Barker, to give just one example, makes similar claim, but for a woman living a century earlier.
Mind you, being a journalist I should know how many repetitive "firsts" there are in the world, in all sorts of areas.
The letters material comes from questia.com, a reasonably cheap subscription site that shows the real possibilities of the web. It boasts the full texts, fully searchable, of a huge number of books, even if it is a sometimes uneven selection with a bias to those out of copyright. Just imagine this, but the entire contents of every new book published, and gradually most of the older ones too: an entire on-line British Library. It must come one day.