Swype Beta has had a nasty habit of forcing you to uninstall, then reinstall at every release, causing all of your custom dictionary words to disappear and enabling the annoying Swype *tick* noise. As it's a system level app being supported on tons of phones these days, one would guess they really didn't want to mess around with potential problems upgrading the software.
Additionally Swype Beta now includes Japanese language options and a prediction engine to learn from what you Swype what you probably are Swyping next.
You can only update if you're in the Swype Beta program, and that generally requires that Swype did not come pre-installed on your phone (Froyo era) or rooting your device and installing a ROM either without Swype or with Swype Beta pre-installed.
So if you're in the Beta, check for updates and let us know how it works on your EVO. If you're stock and have Swype, you'll have to wait for a while until Sprint rolls out another OTA.
[Android Police]