> Is this a halo effect of Stern? Did sirius underestimate
> demand?
Absolutely. There has been a massive shortage of Sirius SKUs across major electronics stores and even a lot of larger online/catalog retailers because of huge Xmas sales. The reason for that was... simply... Howard Stern. I don't listen to him personally, but his drawing power is undeniable.
Stock is returning in major chains over the last 7-10 days.
Not only was December Sirius' best month ever, it was at least 15 times better than any other month in its history.