About When
How Soon
noun
いつ is "when" and 頃 is "about." Combine those together and you have "about when?" or "how soon?"
いつごろ
The reading is the same as the one you learned with the kanji, just rendaku'd.
Tofuguはいつ頃Eブックマーケットに参入するつもりですか？
How soon will Tofugu enter into the e-book market?