This was one of the big UK Supermarket chains. Morrisons the buyer have obviously lost interest or have overlooked the renewal of domain names in the susequent reorganisation. Safeways was about 3 times the size of Morrisons, so it was a difficult aquisition to absorb.
If they ever decide that they want the name back you are in a very difficult position, as whilst you have obtained the domain name, the TM rights are definitely theirs. If they open up a chain of convenience stores, don't be surprised if there is renewed interest in using this name.
Should be traffic but this will fade. Frankly, if you can find a buyer I would cash in as soon as possible.
Best Regards
Dave Wrixon