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#11
Then I'd say you don't have to worry about upgrading to gigabit capability as something "mandatory", either in hardware devices or in cabling. CAT5 cabling and 10/100 NIC's on the computers you're running VLC on should have no problem at all handling 720p streams.
You've obviously been using your setup for a while, and you've just said it's wired. So where does any WiFi capability come into play, if it does, where a question of adequate bandwidth might come up? In fact, why is there a question about "slower switch" or "faster switch"? Where does that come in to your current setup?
In other words, why do you say your setup has a "weak link"? What is the performance degradation symptom you feel you're experiencing, and when?
Also, adding a switch (of either 10/100 or 10/100/1000 capability) would simply be to "port-multiply" and provide more "wired" ports to a location at which you already have one wired port available, if you needed them. So, do you need more wired ports? If so, that's what a switch can buy you and for the nominal price you might as well go with a 10/100/1000 GS105 or equivalent as well as anything limited to 10/100.
But upgrading to a gigabit switch that's fed by a CAT5 cable isn't going to "speed things up" when the PC's connected to as well as the NAS supplying the streams have 10/100 NIC's in them, since everything else is limited to 10/100 network interfaces. In fact, even having gigabit interfaces won't buy you anything if your cabling is still CAT5. So if you're looking to improve over what you currently have, I'd say the CAT5 cabling is the first thing to upgrade.