If you're talking about the 'Intermediate Japanese' text, I rather like it, and while it does review certain grammar points in Genki 1/2, it is most certainly not on the same level. The 'Intermediate Japanese' book focuses a lot more on common usage in everyday society, rather than just 'talking to other college students', so there's more keigo, more oddball grammatical nits, and a hell of a lot more kanji. Once you get past the first few chapters, it gets downright hard. *grin*
Also, if you haven't done so, I recommend checking how much of Genki you absorbed -- I've been going back through Genki 2, and there is the odd word or kanji that I just didn't remember. Better to have the basics down pat. *grin*
My instructor recommended a book titled 「速読用の文化のイペソード」for our summer reading, and it has been quite good as well -- very dense with the kanji, lots of new (useful!) vocabulary, real-world grammar, but light enough to be entertaining, and informative enough to be useful. Explanations for the grammar and vocab are in English, the rest of the book is Japanese, and each chapter has a ◯/× section at the end (with answers in the back) so that you can check your reading comprehension.
Oh, and yes, tapes may be old, but they're still used for things like audio books for a reason -- tapes hold their place.