The current web portal looks similar to the current Photos app found in iOS. You can select multiple photos to either delete or download them, and you can individually favorite, download or delete images as well.
iCloud Photo Library was first unveiled at WWDC, and will let you access any photo you've taken from any device. The images are stored at full resolution in their original formats, including RAW files. iCloud Photo Library will also be able to automatically keep your original high-resolution photos and videos in iCloud and leave behind lightweight versions on your devices. Edits that you make to photos are automatically synchronized across devices if you have iCloud Photo Library enabled. The edits are non-destructive and you can return to the original version if you want.
iCloud Photo Library beta can be enabled from the Settings app in the Photos & Camera section, however in order to access your photos on the web, you must update to iOS 8.1 first, which will be released Monday.