What is the best way to stream m3u8?

Start here for an overview of how to start developing a Roku channel: http://forums.roku.com/viewtopic.php?f=34&t=36014

The latest Roku SDK examples are located on SourceForge: http://sourceforge.net/p/rokusdkexamples/code/HEAD/tree/trunk/rokusdkexamples-code/
You can modify the simplevideoplayer channel to play an m3u8 video.

One approach is to start with something small and simple that just plays a single m3u8 file (assuming the content is in a format supported by Roku) using the roVideoScreen component. Then start adding other components once you get that working (an roSpringboardScreen, for example).

Here's a simple example that just plays an m3u8 HLS video using roVideoScreen, including logging all the events generated. This would be a good way to test whether your videos will play on the Roku:

Sub Main ()
    displayM3U8 ({
                    Streams: [{
                                Url: "http://devimages.apple.com/iphone/samples/bipbop/bipbopall.m3u8"
                                Bitrate: 0
                                Quality: False
                            }]
                    StreamFormat: "hls"
                })
End Sub

Function displayM3U8 (contentItem As Object) As Void
    ui = CreateObject ("roVideoScreen")
    mp = CreateObject ("roMessagePort")
    ui.SetMessagePort (mp)
    ui.SetContent (contentItem)
    ui.Show ()
    While True
        msg = Wait (0, mp)
        logEvent (msg)
        If Type (msg) = "roVideoScreenEvent"
            If msg.IsScreenClosed ()
                Exit While
            EndIf
        EndIf
    End While
End Function

Function logEvent (msg As Object) As Void
    message = ""
    index = 0
    info = Invalid
    If msg = Invalid
        Print timeNow (); "  Timeout"
    Else
        msgType = Type (msg)
        If msgType = "roVideoScreenEvent" Or msgType = "roVideoPlayerEvent"
            If msg.IsStreamStarted ()
                evType = "IsStreamStarted"
                index = msg.GetIndex ()
                info = msg.GetInfo ()
            Else If msg.IsPlaybackPosition ()
                evType = "IsPlaybackPosition"
                index = msg.GetIndex ()
            Else If msg.IsRequestFailed ()
                evType = "IsRequestFailed"
                message = msg.GetMessage ()
                index = msg.GetIndex ()
                info = msg.GetInfo ()
            Else If msg.IsStatusMessage ()
                evType = "IsStatusMessage"
                message = msg.GetMessage ()
            Else If msg.IsFullResult ()
                evType = "IsFullResult"
            Else If msg.IsPartialResult ()
                evType = "IsPartialResult"
            Else If msg.IsPaused ()
                evType = "IsPaused"
            Else If msg.IsResumed ()
                evType = "IsResumed"
            Else If msg.IsScreenClosed ()
                evType = "IsScreenClosed"
            Else If msg.IsStreamSegmentInfo ()
                evType = "IsStreamSegmentInfo"
                message = msg.GetMessage ()
                index = msg.GetIndex ()
                info = msg.GetInfo ()
            Else If msg.IsDownloadSegmentInfo ()    ' Undocumented event
                evType = "IsDownloadSegmentInfo"
                message = msg.GetMessage ()
                index = msg.GetIndex ()
                info = msg.GetInfo ()
            Else If msg.IsListItemSelected ()       ' Undocumented event
                evType = "IsListItemSelected"
                index = msg.GetIndex ()
            Else
                evType = "Unknown"
            EndIf
            timeNowStr = timeNow ()
            tabs = Len (timeNowStr) + Len (msgType) + 4
            Print timeNowStr; "  "; msgType; ". Event Type: "; evType + " [" + msg.GetType ().ToStr () + "]. "; "Index: " + index.ToStr ();
            If message <> ""
                Print ". Message: "; message
            Else
                Print ""
            EndIf
            If Type (info) = "roAssociativeArray"
                For Each key In info
                    infoKey = info [key]
                    If Type (GetInterface (infoKey, "ifIntOps")) = "ifIntOps"
                        Print Tab (tabs); key + ": " + infoKey.ToStr ()
                    Else
                        Print Tab (tabs); key + ": "; infoKey
                    EndIf
                End For
            EndIf
        Else
            ' An event type other than "roVideoScreenEvent" or "roVideoPlayerEvent"
            ' Add additional code here to handle other event types
            Print timeNow (); "  "; msgType; ". Event Type: [" + msg.GetType ().ToStr () + "]"
        Endif
    EndIf
End Function

Function timeNow () As String
    dt = CreateObject ("roDateTime")
    dt.ToLocalTime ()
    hh = Right ("0" + dt.GetHours ().ToStr (), 2)
    mm = Right ("0" + dt.GetMinutes ().ToStr (), 2)
    ss = Right ("0" + dt.GetSeconds ().ToStr (), 2)
    mmm = Right ("00" + dt.GetMilliseconds ().ToStr (), 3)
    Return hh + ":" + mm + ":" + ss + "." + mmm
End Function