No, FLV video is an entirely bitmap-based format.
Given a high enough data rate, it should look quite crisp. If you use 2 pass encoding in Adobe Media Encoder (you have to launch it in standalone mode, 2 pass encoding is not available from within AE) you will get better encoding quality.
I do know of at least one trick and thats to build all the vector stuff in flash and layer in the raster flv. Then make my final swf.
It's not a "trick", it's the proper way to do things. however, an intermediate workaround-ish step between just using FLV and hand-crafing an SWF with vectors could be the use of XFL. Create the text as a PNG image, don't apply any effects in AE to it, just basic transforms, then export as XFL and open the resulting file in Flash if structured properly, other stuff will be rendered to FLV, but your text remain a native PNG with all animation intact...
Ok, thats about what I guessed. Just like to get confirmation on things. That XFL looks pretty handy and advanced. Ill dive into that eventually. Thanks to the both of you.