Well considering that Yahoo! has been trying to purchase half the internet in last few months, something indeed special might be there to announce now. And if its something related to Flickr, it should be awesome then.
I am worried that they might have turned it into a Google+ like social network with streams and feeds and posts and comments with photo as just another element :
Maybe we would see the launch of Yahoo+ on monday! Woo.
That would be a big facepalm moment. Google+'s Handling of photos is really awesome. I tried uploading some 300+ pics and they all look beautiful now. Flickr really needs a magic wand if it wants to stay in the game. And copying G+ would be like :russianroulette:
Flickr still retains the advantage of a pretty awesome unlimited storage package. 500px has a cheaper plan but it is very different in nature.
But Yahoo probably take Google+ as a serious threat to their Flickr business. Loads of pro photographers are dumping Flickr.