Looks like it's out of beta, but still not showing Storm in the list of recommended devices. Here's the latest info from sling:
SlingPlayer Mobile for BlackBerry Out of Beta, 1.0 Now Available From "Sling in the News", A Blog by SlingCommunity News: Sling Community
Per the link here are the devices: (there are also minimum O/S requirements for each device)
"Recommended BlackBerry smartphones
BlackBerry Bold from AT&T
BlackBerry 8820 from AT&T*
BlackBerry Curve 8320 from AT&T*
BlackBerry Curve 8320 from T-Mobile*
BlackBerry Pearl Flip 8220 from T-Mobile*
BlackBerry Pearl 8120 from AT&T*
BlackBerry Curve 8350i from Sprint Nextel*
* Supported by SlingPlayer Mobile when used with Wi-Fi connection"
