If you feel that you cannot wait and want to get a 3G phone go to Best Buy and purchase a refurbished iPhone. I think the 8GB is $99 and the 16GB is $149.
There is no guarantee that a newer iPhone is being released in June, those are all rumors... Then again, they might release a new phone. As for jailbreaking an iPhone that immediately voids your warranty. People are willing to take that risk but each software update cracks it.