If you use SRS's iWOW for iTunes, that there is an issue "with the latest iTunes and OS X Lion updates. The SRS engineering team is quickly addressing the problem and a fix will be available shortly." The symptom (at least on my Mac) is that, when you launch iTunes, an error message appears stating "iWow Error! Internal Error: Could not insert menu bar item.. Error code = 5603."

A work-around is to switch iTunes to run in 32-bit mode, as explained in .

Kirk McElhearn, , describes a "video viewing" bug in Lion running on his iMac: "I started having problems with the computer freezing when I viewed videos. This occurs with all kinds of videos: Flash, H.264, and QuickTime formats, as well as AVIs and MKVs. And we're talking about a serious freeze: the entire screen freezes, except for the cursor." A also covers this matter. As far as I can tell, there is no sure-fire work-around. A cure will have to come from Apple.

that appears specific to MacBook Pro models with Nvidia graphics cards. The symptom is a . MacFixIt suggests the cause may be related to another symptom where a MacBook does not wake up from sleep and remains as a black screen. Again, an thread confirms that the issue is affecting numerous users and that Apple is looking into a solution.

reader rtwendel alerted me to a problem where HDMI fails to work after a Lion upgrade: "Those of us using Mac Minis as media servers connected to Hi-Fi systems with HDMI are unhappy." Confirming this, an extended starts out: "I just installed Lion on my Mac mini and my TV no longer receives a signal over HDMI." A few work-arounds are suggested, such as removing and re-inserting the plug, but none are guaranteed to work.