] From P&P board:

] Would a newly-wed couple of the Darcys' status be expected to host a number of parties, probably in the house in London during the season, to acquaint society with themselves?

It appears that the new Mrs Rushworth held parties, or at least receptions in her London house, and that Mary Crawford expected her to have parties at Sotherton, too--she says something about owing Mrs R. 'many happy hours' (I'm paraphrasing.)