It was rather easy be­cause I did­n't do the hard part (thanks au­thors of pyr­feed!)and now uRSSus has a sim­ple "im­port my sub­scrip­tions from Google Read­er" ac­tion.

All I can say is "it works for me" and "Google sure strips da­ta from the feed­s!".

It will im­port your tags as top-lev­el fold­ers (merged with what­ev­er you al­ready had).

Should be smart enough not to du­pli­cate feeds or fold­er­s.

If a feed is in more than one fold­er, it will show in the first list­ed by google (no idea what the or­der is).