Going HD - Should I dump DirectTV?

I am about to make the leap to HD with a plasma. It seems that cable options are better for HD, with just as much programming plus the locals without having to go through the hassle of an over-the-air antenna. The only sports package I get is the MLB extra innings, which is also available via cable. I have seen a couple of threads on the AVS forum about DirectTV adding satelites, requiring a bigger additional dish, etc. The only thing I am unsure about is Tivo. Is Tivo available for non HD on cable? It seems like cable is a better option for HD right now? Any help is appreciated.
My digital channels and digital HD channels improved dramatically when I swapped HD cable boxes. I previously had a Scientific Atlanta HD XXXX (can't remember the exact model). I swapped it for a new PACE box that supported DVI (but I'm still using the component output, like before). The pixelization on non-HD digital channels went away. It also "upconverts" to either 480p, 720p or 1080i.


Sean's comment that it depends on local conditions matches what I've heard. A Comcast repair guy told me that I shouldn't bother w/their HD yet, because of problems in my neighborhood.
As a DirectTV / Tivo user, I'm reluctant to switch to any cable-provided DVR that doesn't include Tivo and two tuners. IMHO, the Tivo software is what keeps my family happy.
Unfortunately, that leaves me waiting to get HD. Given that the Samsung DirectTV/Tivo requires the new oval-shaped dish and even on sale, $850 is just too high. Hoping that by next Christmas, $300-400 will buy one of these or a competing model from Hughes etc. Considering all the ads on DTV pushing for HD, you'd think the hardware to support it would be more prevelant, and not require you to take steps backwards regarding Tivo, etc. Cheers,
I have recently upgraded to HDTV on Comcast. Continue to think anout sat. One advantage of the Comcast HD-PVR is that it only costs an additional $5 per month, instead of the $850-$1000 for HD Tivo. Also, the HDTV reception noticably improved when I replaced Comcast component cables with aftermarket (Audioquest YIQ-1 $150 for 2 m).
The cost factor is indeed one of the reasons. The Comcast box is a Motorola and is rentable for cheap. Considering the pace of technology change, that $850-$1000 vs $5/month is a considerable factor. Plus Comcast will give you the credit for trading in a dish and sat box. In New England with snow issues and teh sat being pretty low in the sky, I had major compression, pixelization, and lack of availability issues. Obviously, others have gone the other route and seem to be very happy. YMMV.
I have COX cable and the HDTV channels have a green color tint and the sound of each channel is at different volumes. HDTV pixels sometimes as they shift bandwidth around. Check out VOOM for the largest amount of HDTV programming. I use to own Dish HDTV and it looked way better than my COX cable HDTV.