For what it's worth, I helped a friend upgrade from an ancient amp and CRT television to a new HD LCD panel, new Onkyo receiver ($250 including all the HDMI goodness), and matching Blu-ray player (cheap Samsung model). We bought the cheapo HDMI cables (3 for $10 at Fry's, but over in the computer section rather than in the TV section where they only carry overpriced Monster cables). We ended up with some snow on the HDMI connection from the Blu-ray which was completely fixed by going to a different cable from the same bag.

Conclusion: it's certainly true that cheapo HDMI cables sometimes cause problems, but there's still no reason to spend the bucks on fancy expensive ones.