it all comes down to what you want to do with the camera.
1.  can your computer/software handle HD/HDV footage?
2.  are you an experienced film maker? don't wan to sink a good chunk of money into a camera you don't need at the moment.
3.  If you're hard set of an HDV cam, then check out the canon HV20.  Used properly, this is a KILLER camera for a great price.  You just have to know how to use it properly.  Great for run and gun shooting with friends.
4.  Look at the other options.  Standard Def is on its way out, so are you going to regret getting a GL2?  I guarantee that if you aren't 100% sure about it, you will be wanting an HD cam as soon as you get the GL2.  It's only natural to want better, unless you're content with the GL2 for a while.
5.  There are HUGE differences between the two cameras.  The A1 is an amazing camera when used properly.  All this "HDV sucks" talk is a load of shit.  It all comes down to the film maker and what kind of image they can produce with the camera.   I have seen A1 footage that BLOWS good HVX footage out of the water.  As well as Fx1 footage.  Like I said before, it's all in how you shoot the shot and how good of an eye you have.
hope this helps