Well, there was this spotting submitted to Gawker:
"While waiting for our table at La Esquina, I saw Eva Mendes heading for the bathroom with a greasy man trailing behind her. First thought was, 'What’s she doing with this greaseball?...' Quickly realized said greaseball was Joaquin Phoenix, and he mysteriously went from greasy to really hot. He appeared to be either very nervous or extremely coked up; also, he was short."
Then there was Joaquin's "I love you..." message when the nominations for Best Actor in a Leading Role were read out during this year's Oscar telecast. Many interpreted it as "I love you, River..." but could it have been "I love you, Eva..."? Hmm.
And finally, Perez Hilton has posted these photos of the two: