A leaked ROM update for the AT&T Tilt2 surfaced the other day and we've had a few days to tinker with it. The ROM is based on the 21887 build of Windows Mobile 6.5 and runs HTC Sense 2.5. It also has an updated radio (126.96.36.199).
Compared to the original shipped ROM for the Tilt2, the updated ROM is noticeably more responsive. Sense 2.5 flows smoothly and apps are pulled up with little or no delay. ROM Chefs, such as NRGZ28, have already begun to incorporate parts of this build into their cooking. The ROM has potential but as is, still has a ways to go before it can be stamped "official" ROM.
As is, it's a nice building foundation but you will need to install or update a few items. Net CF is an older version (v2.1) and to run more current apps and modifiers, you'll need to install a more current version (v3.5). Neither BING nor Google Maps is preloaded. Office Mobile is an older release but the 2010 release is free over at the Marketplace. Nothing critical but you'll need to spend some time loading some additional apps or updated versions.
To address the bloatware, you can use Crud Scraper (requires .NET CF 3.5) to free up to 39mb of memory. I choose BSB Tweaks to help optimize the Tilt2 but other tweaks are available to help boost performance. I also installed Brian's Taskbar (requires SdkCerts installed) to help add some color to my notification icons.
Remember, a ROM update will wipe your device clean so a data back-up is highly encouraged. Also, read up on any modifiers you install. Check and make sure there aren't any required .cab files (e.g. .NET CF , SdkCerts, etc.) because without them you can crash your Windows Phone.
All in all, I like the direction AT&T has taken with this update. Just remember all is not lost if you update and don't like what you see. The original Tilt2 ROM is still available over at HTC's Support Site.