Too many changes for a short reply. Many very good, a few not so good. Depends on what you want to do how much the downside affects you, but you certainly need powerful hardware to get the best from PPro - much more demanding than for earlier versions in this respect.
You could download the trial version and see for yourself, or look up the feature list on the Adobe site. Note that XP is required. Other OS not acceptable, nor are non-SSE processors.