I concur with the others. Not only will you be getting on at the ground floor, so to speak, but you'll be doing so at MSRP prices, instead of the ridiculously inflated eBay prices 1e seems to be going for.
The only reason to buy up 1e now would be if you REALLY REALLY want the figures to use with 2e's conversion kit, but that's a lot of money if all you want is the plastic. It would probably be far cheaper to look at proxy figures if you still want the conversion kit.
Don't get me wrong, 1e was a great game despite its flaws and I'm sure there are some veteran players who will stick to what they know rather than upgrade, but really, 2e is better in just about every way from what I've been seeing in the previews so far.