Yes, The L in the model string means Cloud services.
Honestly, IMO, I would go with the 826L/845L. The 645 and the 657 have been on the market for a few years now and FW support is slowing down and I presume these routers will go into Phased out status sooner than the 826L/845L will. The 657 has had limited FW version releases, even for me, it's been a good router however there are a couple of issues that I've been trying to get fixed by D-Link and not sure if that will come about. Here in the NA region, the 645 is a good router and has had some good updates however I believe that has come to an end unless there is a critical problem found.
The EU region is a bit separate on how they handle there products and FW issues from other regions so I don't know what, if any releases are forthcoming for the 645 and 657 in the EU region.
I recommend that you give the 826L/845L a review and check it out. Just because they have the the Cloud services features doesn't mean you have to use it. You can leave the router un-registered for that. You might find it handy in the future.
I have the 826L router here and do enjoy it. I just don't have a TV that has network abilities so I really can't test that. I can test some with my Boxee Box as a streamer.