Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of satellite radio monopoly Sirius XM Radio (Nasdaq: SIRI) plunged as far as 13% in a sudden rush of downside action this morning but have since recovered to a 2% gain on the day.

So what: A mixed car-sales report shouldn't dunk Sirius like this, and a programming deal with the NHL should be positive news -- unless Sirius investors hate hockey, of course. A more likely culprit behind this temporary drop is SeekingAlpha, which published a series of Sirius-bashing articles this morning.

Now what: Despite its nearly $6 billion market cap and prodigious share volume, Sirius remains a nervy penny stock until further notice. Sirius 2.0 can't come fast enough for this perennially beleaguered operator, especially while rivals Spotify and Pandora Media (NYSE: P) go from strength to strength. You know, a reverse split wouldn't hurt anybody but could keep the Nasdaq off Sirius' back for the foreseeable future. Wouldn't life be nicer without a constant delisting threat hanging over the stock -- and an easily erased one at that?

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