Mactubes is a guide for youtube environment.

MacTubes is a browser. But not ordinary. As you probably already had, it doesn’t browse our web pages. And he browses us youtube-videos. And he does it easily and naturally :-) Like any other browser, it can:

1. Search by author, tags, titles.
2. Choose a country “in which to search”
3. Show videos in flv (low) or in mp4 (high) quality
4. Download in the quality in which we need
5. Create Bookmarks, Subscriptions. Group everything as needed by the user.
6. He has his own, built-in daunloader. Which supports n-th number of downloads.
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In general, in my opinion, all that is needed from a video browser is that it can :-) Besides, it is free.
You can download it here: www.macupdate.com/info.php/id/28608/mactubes