As long as you can make your photo library appear as a network drive on Windows 8 (CIFS, SaMBa, etc), Picasa will be a nice way to view the photos.
You can group photos together. Create a New Album and dragging photos to that album. The files do not move, it is just metadata.
Tag photos You go to the picture and adds tags
- Files remain on network drive
Your photos remain on the network drive, they are not copied to the local computer. If you delete the photo in Picasa, it is deleted from the source as well.
- Meta data remains on the network drive
The default location for the database is on the local machine, but you can move the database to the network drive via Tools > Experimental > Choose database location...
As long as you can have each workstation access the same drive letters and mapped network drive, you can share the database with the different workstations. When you add a second workstation to share the database, you have to rename the Picasa database folder to something else. Then on the second workstation, move the database to the same directory. Then exit out of Picasa, delete the newly created folder, and rename the original Picasa database folder to its original name. This way, all instances of Picasa point to the same network folder.
Each time there is a new version of Picasa, you must go through the same process as described above.