Before Google launched Google plus, Picasa users only have 1 GB of storage for the photos uploaded to the service and if you want more space, pay for the additional disc space to store more photos online. Google actually offers 5 plan to choose from; $5.00/yr for 20 GB, $20.00/yr for 80 GB, $50.00/yr for 200 GB, $100.00/yr for 400 GB and $256/yr for 1 TB for storage.
Now that Google launched Google Plus, looks like everything about photo storage will change. Since Google will provide you virtually unlimited space to store your photos on Picasa. To use the unlimited photos and videos, your photos should not be larger than 2,048 by 2,048 pixels or else Google will automatically be resize them to 2048 pixels (on their longest edge), and the videos should not be longer than 15 minutes (up to 1080p).
There’s no telling what will be the impact of Google+ for people who upgraded their storage and for the business but it looks like they’ll be discontinuing this soon. The Picasa storage does not only count the photos uploaded, it also being shared with other Google products like Gmail, Picasa Web Albums, Google Docs and Google Maps.