Here's what you see when accessing the Nokia Store from any Symbian device right now (and yes, it goes straight here, via a redirect!):
So far, all the content seems to be free or freemium - it's not clear whether this is by design or just that payment systems aren't in place yet.
Of course, most Symbian enthusiasts have been ignoring the Nokia Store for ages anyway, with a variety of DIY approaches, not least the AppList Store, plus custom firmware (e.g. Delight) as the base, freeing devices from Nokia signing and out of date firmware builds.
There's no reason not to have a browse around the new Opera Store, of course, it serves up free SISx files as well as the next emporium, though do note that your purchase history with Nokia over the years has been nullified, of course.
If there are particular commercial applications or games that you've bought and cannot now reinstall when needed, there may (ahem) be other download sources - of varying legality, so be careful what else you pick up at the same time. Thankfully, most applications of any note have now been made free anyway, meaning that their SIS files are archived in many places and usually available in AppList - or indeed in the Opera Store perhaps...
End of an era, of course. The Nokia Store, implemented in a mixture of HTML and Qt routines, never set the world alight and was always a little clunky and a little buggy - a native Symbian implementation would have been much better, but at the time Nokia had its eyes on Meego and cross-platform everything.
Comments welcome on all this!