Mr. Bly's collection includes the two most famous poems by Rilke, Der Panther ("The panther") and Herbsttag ("October Day"), but mostly it reflects the editor's personal taste. For example, he omits the Duino Elegies because, among other things, he is not convinced they belong to Rilke's best work: "There's something about them that is admirable but not likeable."Bly has a good sense for the troubled life of Rilke and the inner strength that enabled Rilke to produce his art (a situation not unlike that of Hermann Hesse, whose poems Rilke once classified as being "on the verge of art"). Despite Rilke's neuroticism, his rootlessness, and his difficult relationships, for Bly, Rilke "stands for toughness, freedom from self-pity, ability to work, whatever one's life situation."
Although Bly states that he wants to be true to the sound of the poems, his translations are quite matter-of-fact and lose a lot of the lyrical qualities of the German original. If you are looking for a translation that captures the spirit and sound of Rilkes poetry better than Bly's efforts, try Stephen Mitchell's The Selected Poetry of Rainer Maria Rilke.
To give you an idea of the difference in quality, let me compare the translations of the first stanza of the first of the Sonnets to Orpheus. The original in German is: Da stieg ein Baum. O reine Uebersteigung! / O Orpheus singt! O hoher Baum im Ohr! / Und alles schweigt. Doch selbst in der Verschweigung / ging neuer Anfang, Wink und Wandlung vor.
Bly translates: A tree rising. What a pure growing! / Orpheus is singing! A tree inside the ear! / Silence, silence. Yet new buildings, / signals, and changes went on in the silence. (nice try at the "s" "s" sounds, but why does he drop the "tall" - a nice alliteration to "tree"? And isn't it a bit cruel to the English language to write "buildings ... went on in the silence"?)
Mitchell translates: A tree ascended there. Oh pure transcendence! / Oh Orpheus sings! Oh tall tree in the ear! / And all things hushed. Yet even in that silence / a new beginning, beckoning, change appeared.
To give you an idea of the genius of the second translation, consider the following: "stieg" means "rose", but "stieg auf" means "ascended"; "ging...vor" means "happened", but "ging...hervor" means "appeared". Mitchell probed the connotations of the German verbs, and pushed their meaning - within the limits of the German original - to achieve a more poignant, vibrating, powerful quality in the English translation. Also, his use of alliteration is much closer to the spirit of the German original. Unable to keep the alliteration of Oh-Ohr, he employs tall-tree and and-all. On a personal note, I very much admire the choice of the verb "hushed" with its "shshsh" sound as a translation for the most important noun in the first stanza: "Verschweigung" (a neologism of "verschweigen" (to conceal, to be silent), and "Verzweigung"(branching)). The "shshsh" sound keeps the many "s" and "sch" sounds you can hear when you read the first stanza (in German) aloud, and it is just as evocative of the sound of wind in a tree as the German original. That's an amazing achievement.