Okay, I am new to these forums so please forgive me if this has already been talked about.

The other day I was riding around on Shadowmere when I spotted a wayshrine. Figuring I could use the blessing I rode up onto the shrine and dismounted. Still being very close to Shadowmere I activated the shrine but didn't receive the blessing! Instead Shadowmere got it. When I then mounted her she took off like a thunderbolt. She wasn't just fast, she was too fast for the xbox to handle it. I got from Anvil to Cheydinhal in under 3 minutes and when I ran off of hills I wouldn't fall but go straight into the air. Its been 3 days of playing now and the blessing still hasn't worn off so I'm thinking it might be permanent. Has anybody else encountered this?

Not a glitch, an exploit.

Wayshrines of Akatosh provide a boost to an actors Speed for 600 seconds (10 minutes) real-time. If it has become permanent, well, I'm not sure you can do much but restore a previous save (since you're on the Xbox) if you don't want to keep your uber-fast horsie.