You're disappointed that HTC is making a slider with a smaller screen? The pictures I've seen make the front of the device look very EVO-like in my opinion. What exactly about the EVO makes it so desireable? The 4.3" screen? The outer casing design?
There is supposed to be a Verizon Droid Incredible HD coming out that will have LTE ability and a 4.3" screen as well as a really fast processor.
What phone do you have now, the HTC EVO? If so, the phone is only about a half a year old. Are you already in the market for a new phone?
I highly doubt that HTC has abandoned making candybar smartphones, so don't get upset that you'll never have a new device like the original EVO again. I think that what HTC/Sprint is doing is similar to Verizon. They create a name brand: EVO (similar to the Droid brand name). Within this brand, they have an original device, and then they expand the line-up to include more offerings.
As an example, look at the Droid. That was followed by the Droid Incredible, Droid X, Droid 2, Droid 2 Global, and Droid Pro. I believe Sprint/HTC will be taking a similar path, so you can probably expect more EVO branded devices coming in 2011.