Batarian bartender, but it appears that Liara T'soni may return to fighting form in future Mass Effect 2 DLC. Tehpwnage explains that extracted sound files from the PC version of the game allegedly allude to a quest where Shepard's former companion (and possible lover) confronts the Shadow Broker.
If the sound clips are authentic, it's unclear whether Liara's Shadow Broker sub-plot will be handled using the same structure as other Mass Effect 2 characters, or if it'll be part of something more like BioWare's Dragon Age: Origins -- Awakening, thus taking place after the events of the core game. It'd be nice to have Liara back on the team, but given the weight bestowed upon the Shadow Broker in the Mass Effect universe, it'd be awkward if he/she/it were dispatched through a simple "loyalty mission" -- although it may feel less abrupt for transmedia consumers of the comic. Those interested in the spoilerish sound clips can give them a listen after the break.